+ All Categories
Home > Documents > CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and...

CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and...

Date post: 12-Mar-2021
Category:
Upload: others
View: 3 times
Download: 0 times
Share this document with a friend
70
CENGAGE / G TEWANI MATHS SOLUTIONS CHAPTER SEQUENCES AND SERIES || ALGEBRA Download Doubtnut Today Ques No. Question 1 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction Write down the sequence whose nth term is and (ii) Watch Free Video Solution on Doubtnut 2 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction Find the sequence of he numbers defined by Watch Free Video Solution on Doubtnut 3 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction Write the first three terms of the sequence defined by . Watch Free Video Solution on Doubtnut 4 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction Consider the sequence defined by If then find the value of Watch Free Video Solution on Doubtnut 5 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction The Fibonacci sequence is defined by and Find Watch Free Video Solution on Doubtnut 6 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction A sequence of integers satisfies for . Suppose the sum of first 999 terms is 1003 and the sum of the first 1003 terms is 99. Find the sum of the first 2002 terms. Watch Free Video Solution on Doubtnut 7 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression
Transcript
Page 1: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

CENGAGE / G TEWANI MATHS SOLUTIONS

CHAPTER SEQUENCES AND SERIES || ALGEBRA

Download Doubtnut Today

Ques No. Question

1

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction

Write down the sequence whose nth term is and (ii)

Watch Free Video Solution on Doubtnut

2

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction

Find the sequence of he numbers defined by

Watch Free Video Solution on Doubtnut

3

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction

Write the first three terms of the sequence defined by .

Watch Free Video Solution on Doubtnut

4

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction

Consider the sequence defined by If then find the value of

Watch Free Video Solution on Doubtnut

5

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction

The Fibonacci sequence is defined by and Find

Watch Free Video Solution on Doubtnut

6

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Introduction

A sequence of integers satisfies for . Suppose the sum of first 999 terms is 1003 and the sum of thefirst 1003 terms is ­99. Find the sum of the first 2002 terms.

Watch Free Video Solution on Doubtnut

7 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

2n /n [3 + ( − 1)n]/3n

an = , whe ∩ isodd , whe ∩ iseven1

n

1

n

a1 = 2, an+1 =2an + 3

an + 2

an = an2 + bn + ⋅ a1 = 1, a2 = 5, anda3 = 11, a10.

1 = a1 = a2 an = an−1 + an−2 ,n > 2. , f or n = 5.an+1

an

a1 + a2 + ...... + an an+2 = an+1 − an n ≥ 1

Page 2: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

Show that the sequence 9, 12, 15, 18, ... is an A.P. Find its 16th term and the general term.

Watch Free Video Solution on Doubtnut

8

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Show that the sequence is an A.P. Find the nth term.

Watch Free Video Solution on Doubtnut

9

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the sum of terms of the sequence

Watch Free Video Solution on Doubtnut

10

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

How many terms are there in the A.P. 3, 7, 11, ... 407?

Watch Free Video Solution on Doubtnut

11

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., the find the value of

Watch Free Video Solution on Doubtnut

12

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

In a certain A.P., 5 times the 5th terms is equal to 8 times the 8th term. Then prove that its 13th term s 0.

Watch Free Video Solution on Doubtnut

13

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the term of the series which is numerically the smallest.

Watch Free Video Solution on Doubtnut

14

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The sum of the first four terms of an A.P. is 56. The sum of the last four terms is 112. If its first term is 11, then find the number of terms.

Watch Free Video Solution on Doubtnut

15

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Given two A.P. and Then find the number of terms which are identical.

Watch Free Video Solution on Doubtnut

16 CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Consider two A.P. s: Find the number of common term. Also find the last common term.

log a, log(ab), log(ab2), log(ab3),

n (an), wherean = 5 − 6n, n ∈ N .

a, b, c, d, e a − 4b + 6c − 4d + e.

25, 22 , 20 , 183

4

1

2

1

4

2, 5, 8, 11......T60 3, 5, 79, .........T50.

S1 : 2, 7, 12, 17, 500terms andS1 : 1, 8, 15, 22, 300terms

Page 3: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

Watch Free Video Solution on Doubtnut

17

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If pth, qth, and rth terms of an A.P. are respectively, then show that

Watch Free Video Solution on Doubtnut

18

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., then prove that are also in A.P.

Watch Free Video Solution on Doubtnut

19

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If form an A.P., then prove that are also in A.P.

Watch Free Video Solution on Doubtnut

20

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., then prove that the following are also in A.P.

Watch Free Video Solution on Doubtnut

21

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., then prove that the following are also in A.P.

Watch Free Video Solution on Doubtnut

22

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., then prove that the following are also in A.P.

Watch Free Video Solution on Doubtnut

23

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sum of three numbers in A.P. is 24 and their product is 440, find the numbers.

Watch Free Video Solution on Doubtnut

a, b, c, (a − b)r + (b − c)p + (c − a)q = 0

(b + c − a)/a, (c + a − b)/b, (a + b − c)/c 1/a, 1/b, 1/c

a, b, c ∈ R + a + 1/(bc), b + 1/(1/ac), c + 1/(ab)

a, b, c a2(b + c), b2(c + a), c2(a + b)

a, b, c , ,1

√b + √c

1

√c + √a

1

√a + √b

a, b, c a( + ), b( + ), c( + )1

b

1

c

1

c

1

a

1

a

1

b

Page 4: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

24

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Show terms of an A.P. is equal to twice the mth terms.

Watch Free Video Solution on Doubtnut

25

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Divide 32 into four parts which are in A.P. such that the ratio of the product of extremes to the product of means is 7:15.

Watch Free Video Solution on Doubtnut

26

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The digits of a positive integer, having three digits, are in A.P. and their sum is 15. The number obtained by reversing the digits is 594 less than theoriginal number. Find the number.

Watch Free Video Solution on Doubtnut

27

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sum of the series 2, 5, 8, 11, ... is 60100, then find the value of

Watch Free Video Solution on Doubtnut

28

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

In an A.P. if , then find the value of in terms of

Watch Free Video Solution on Doubtnut

29

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Prove that the sum of number of terms of two different A.P. s can be same for only one value of

Watch Free Video Solution on Doubtnut

(m + n)thand(m − n)th

n.

S1 = T1 + T2 + T3 + .... . + Tn(nodd).S2 = T2 + T4 + T6 + ......... + Tn−1 S1 /S2 n.

n n.

Page 5: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

30

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

In an A.P. of 99 terms, the sum of all the odd­numbered terms is 2550. Then find the sum of all the 99 terms of the A.P.

Watch Free Video Solution on Doubtnut

31

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the degree of the expression

Watch Free Video Solution on Doubtnut

32

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the number of terms in the series the sum of which is 300. Explain the answer.

Watch Free Video Solution on Doubtnut

33

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the sum of all three­digit natural numbers, which are divisible by 7.

Watch Free Video Solution on Doubtnut

34

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Prove that a sequence in an A.P., if the sum of its terms is of the form are constants.

Watch Free Video Solution on Doubtnut

35

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sequence forms an A.P., then prove that

Watch Free Video Solution on Doubtnut

(1 + x)(1 + x6)(1 + x11)....... . (1 + x101).

20, 19 , 18 ...1

3

2

3

n An2 + Bn, whereA,B

a1, a2, a3, an, . a12 − a22 + a32 + + a42 = (a12 − a2n2)n

2n − 1

Page 6: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

36

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the sum of first 24 terms of the A.P. if it is inown that

Watch Free Video Solution on Doubtnut

37

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the arithmetic progression whose common difference is nonzero the sum of first terms is equal to the sum of next terms. Then, find the ratio of thesum of the terms to the sum of next terms.

Watch Free Video Solution on Doubtnut

38

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The sum of terms of two arithmetic progressions are in the ratio Find the ratio of their 18th terms.

Watch Free Video Solution on Doubtnut

39

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Insert five arithmetic means between 8 and 26. or Insert five numbers between 8 and 26 such that the resulting sequence is an A.P.

Watch Free Video Solution on Doubtnut

40

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If eleven A.M. ‘s are inserted between 28 and 10, then find the number of integral A.M. ‘s.

Watch Free Video Solution on Doubtnut

41

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Between 1 and 31 are inserted arithmetic means of that the ratio of the 7th and means is 5:9. Find the value of Or Between 1 and 31 , numbers have been inserted in such a way that the resulting sequence is an A.P. and the ratio of 7th and numbers is 5:9. Find the value of

Watch Free Video Solution on Doubtnut

a − 1, a2, a3, a1 + a5 + a10 + a15 + a20 + a24 = 225.

3n n2n 2n

n 5n + 4: 9n + 6.

m (m − 1)th m.

m (m − 1)thm.

Page 7: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

42

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If is A.M. between then find the value of .

Watch Free Video Solution on Doubtnut

43

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Which term of the G.P.

Watch Free Video Solution on Doubtnut

44

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The first terms of a G.P. is 1. The sum of the third and fifth terms is 90. Find the common ratio of the G.P.

Watch Free Video Solution on Doubtnut

45

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If then show that are in G.P.

Watch Free Video Solution on Doubtnut

46

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The fourth, seventh, and the last term of a G.P. are 10, 80, and 2560, respectively. Find the first term and the number of terms in G.P.

Watch Free Video Solution on Doubtnut

47

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Three numbers are in G.P. If we double the middle term, we get an A.P. Then find the common ratio of the G.P.

Watch Free Video Solution on Doubtnut

an + bn

an−1 + bn−1aandb, n

2, 1, 1/2, 1/4. . . . . . . is1/128?

= = (x ≠ 0),a + bx

a − bx

b + cx

b − cx

c + dx

c − dxa, b, c, andd

Page 8: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

48

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are inA.P., show that the pth, qth, and rth terms of any G.P. are in G.P.

Watch Free Video Solution on Doubtnut

49

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P. prove that are in G.P.

Watch Free Video Solution on Doubtnut

50

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P. show that .

Watch Free Video Solution on Doubtnut

51

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Three non­zero numbers are in A.P. Increasing by 1 or increasing by 2, the numbers are in G.P. Then find

Watch Free Video Solution on Doubtnut

52

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The sum of three numbers in GP. Is 56. If we subtract 1, 7, 21 from these numbers in that order, we obtain an arithmetic progression. Find the numbers.

Watch Free Video Solution on Doubtnut

53

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P. are in G.P and are in G.P. Prove that are in G.P.

Watch Free Video Solution on Doubtnut

p, q, andr

a, b, c, d (an + bn), (bn + cn), (cn + dn)

a, b, candd (ab + bc + cd) = (a2 + b2 + c2)(b2 + c2 + d2)

a, b, andc a c b.

a, b, c b, c, d , ,1

c

1

d

1

ea, c, e

Page 9: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

54

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the continued product o three numbers in a G.P. is 216 and the sum of their products in pairs is 156, find the numbers.

Watch Free Video Solution on Doubtnut

55

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The sum of some terms of G.P. is 315 whose first term and the common ratio are 5 and 2, respectively. Find the last term and the number of terms.

Watch Free Video Solution on Doubtnut

56

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Determine the number of terms in a G.P., if

Watch Free Video Solution on Doubtnut

57

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let e the sum, the product, adn the sum of reciprocals of terms in a G.P. Prove that

Watch Free Video Solution on Doubtnut

58

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the sum to terms of the sequence

Watch Free Video Solution on Doubtnut

59

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Prove that the sum to terms of the series

Watch Free Video Solution on Doubtnut

a1 = 3, an = 96, andSn = 189.

S P R n P 2Rn = Sn.

n (x + 1/x)2, (x2 + 1/x)

2, (x3 + 1/x)

2, ,

n 11 + 103 + 1005 + is(10/9)(10n − 1) + n2.

Page 10: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

60

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the sum of the following series: terms. terms.

Watch Free Video Solution on Doubtnut

61

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Prove that in a sequence of numbers 49,4489,444889,44448889 in which every number is made by inserting 48­48 in the middle of previous as indicated,each number is the square of an integer.

Watch Free Video Solution on Doubtnut

62

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If is a function satisfying for all such that and find the value of .

Watch Free Video Solution on Doubtnut

63

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If is a polomial in , then find possible value of

Watch Free Video Solution on Doubtnut

64

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the sum of the following series:

Watch Free Video Solution on Doubtnut

65

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If each term of an infinite G.P. is twice the sum of the terms following it, then find the common ratio of the G.P.

Watch Free Video Solution on Doubtnut

5 + 55 + 555 + ... → n . 6 + . 66 + . 666 + ... → n

f f(x + y) = f(x) × f(y) x, y ∈ N f(1) = 3n

∑x=1

f(x) = 120, n

p(x) = (1 + x2 + x4 + + x2n−2)/(1 + x + x2 + + xn−1) x n.

(√2 + 1) + 1 + (√2 − 1) + ∞

Page 11: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

66

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If then prove that

Watch Free Video Solution on Doubtnut

67

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Prove that

Watch Free Video Solution on Doubtnut

68

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The sum of infinite number of terms in G.P. is 20 and the sum of their squares is 100. Then find the common ratio of G.P.

Watch Free Video Solution on Doubtnut

69

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If is the geometric mean of then prove that

Watch Free Video Solution on Doubtnut

70

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Insert four G.M.’s between 2 and 486.

Watch Free Video Solution on Doubtnut

71

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the product o three geometric means between 4 and 1/4.

Watch Free Video Solution on Doubtnut

x = a + a/r2 + ∞, y = b − b/r + b/r2 − ∞, andz = c + c/r2 + c/r4 + ∞, xy/z = ab/ ⋅

61 / 2 × 61 / 4 × 61 / 8∞ = 6.

G xandy + =1

G2 − x2

1

G2 − y2

1

G2

Page 12: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

72

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find two numbers whose arithmetic mean is 34 and the geometric mean is 16.

Watch Free Video Solution on Doubtnut

73

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If A.M. and G.M. between two numbers is in the ratio then prove that the numbers are in the ratio

Watch Free Video Solution on Doubtnut

74

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If is the A.M. of and and the two geometric mean are and then prove that

Watch Free Video Solution on Doubtnut

75

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The 8th and 14th term of a H.P. are 1/2 and 1/3, respectively. Find its 20th term. Also, find its general term.

Watch Free Video Solution on Doubtnut

76

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the 20th term of a H.P. is 1 and the 30th term is ­1/17, then find its largest term.

Watch Free Video Solution on Doubtnut

77

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in H.P., then prove that and , are in A.P.

Watch Free Video Solution on Doubtnut

m :n (m + √m2 − n2) :(m − √m2 − n2).

a b c G1 G2, G31 + G3

2 = 2ab ⋅

a, b, candd (b + c + d)/a, (c + d + a)/b, (d + a + b)/c (a + b + c)/d

Page 13: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

78

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The mth term of a H.P is and the nth term is . Proves that its rth term is

Watch Free Video Solution on Doubtnut

79

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If and are in G.P. then show that are in H.P.

Watch Free Video Solution on Doubtnut

80

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If be in G.P. and in H.P. then find the value of .

Watch Free Video Solution on Doubtnut

81

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If first three terms of the sequence are in geometric series and last three terms are in harmonic series, then find the values of

Watch Free Video Solution on Doubtnut

82

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Insert four H.M.’s between 2/3 and 2/13.

Watch Free Video Solution on Doubtnut

83

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If is the harmonic mean between then find the value of

Watch Free Video Solution on Doubtnut

n m mn/r.

a > 1, b > 1 c > 1 , , and1

1 + (log)ea

1

1 + (log)eb

1

1 + (log)ec

a, b, andc a + x, b + x, andc + x x(a, bandcaredist ∈ ctνmbers)

1/16, a, b,1

6aandb.

H PandQ H /P + H /Q.

Page 14: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

84

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If nine arithmetic means and nine harmonic means are inserted between 2 and 3 alternatively, then prove that (where is any of theA.M.'s and the corresponding H.M.)

Watch Free Video Solution on Doubtnut

85

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

The A.M. and H.M. between two numbers are 27 and 122, respectively, then find their G.M.

Watch Free Video Solution on Doubtnut

86

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

If the A.M. between two numbers exceeds their G.M. by 2 and the GM. Exceeds their H.M. by 8/5, find the numbers.

Watch Free Video Solution on Doubtnut

87

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the series terms.

Watch Free Video Solution on Doubtnut

88

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of terms of the series

Watch Free Video Solution on Doubtnut

89

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the series upto terms.

Watch Free Video Solution on Doubtnut

A + 6/H = 5 AH .

1 + 3x + 5x2 + 7x2 + → n

n 1 + + + + .4

5

7

5210

53

1 + 3x + 5x2 + 7x3 + .......... n

Page 15: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

90

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum to infinity of the series

Watch Free Video Solution on Doubtnut

91

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum to terms of the series

Watch Free Video Solution on Doubtnut

92

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the series

Watch Free Video Solution on Doubtnut

93

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the series up to terms.

Watch Free Video Solution on Doubtnut

94

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the series

Watch Free Video Solution on Doubtnut

95

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of first terms of the series is even is odd

Watch Free Video Solution on Doubtnut

12 + 22x + 32x2 + ∞.

n 1 × 2 × 3 + 2 × 3 × 4 + 3 × 4 × 5 + .

1 × n + 2(n − 1) + 3 × (n − 2) + + (n − 1) × 2 + n × 1.

+ + +13

1

13 + 23

1 + 3

13 + 23 + 33

1 + 3 + 5n

313 + 323 + + 503.

n 13 + 3 × 22 + 33 + 3 × 42 + 53 + 3 × 62 + when n n

Page 16: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

96

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum to terms of the series

Watch Free Video Solution on Doubtnut

97

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If then find the sum

Watch Free Video Solution on Doubtnut

98

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If then find the sum of .

Watch Free Video Solution on Doubtnut

99

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum to terms of the series

Watch Free Video Solution on Doubtnut

100

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the following series to terms

Watch Free Video Solution on Doubtnut

101

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum to terms of the series

Watch Free Video Solution on Doubtnut

n 12 − 22 + 32 − 42 + 52 − 62 + . . . .

n

∑r=1

Tr = n(2n2 + 9n + 13),n

∑r=1

√Tr.

n

∑r=1

Tr = (3n − 1),n

∑r=1

1

Tr

n 3 + 15 + 35 + 63 +

n 5 + 7 + 13 + 31 + 85 +

n 1/(1 × 2) + 1/(2 × 3) + 1/(3 × 4) + + 1/n(n + 1).

Page 17: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

102

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum

Watch Free Video Solution on Doubtnut

103

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum to terms of the series

Watch Free Video Solution on Doubtnut

104

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum to terms of the series that means find

Watch Free Video Solution on Doubtnut

105

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum

Watch Free Video Solution on Doubtnut

106

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum

Watch Free Video Solution on Doubtnut

107

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum where n!= .

Watch Free Video Solution on Doubtnut

n

∑r=1

.1

(ar + b)(ar + a + b)

n 3/(12 × 22) + 5/(22 × 32) + 7/(32 × 42) + .

n + + + ..........1

1 + 12 + 142

1 + 22 + 243

1 + 32 + 34tr =

r

r4 + r2 + 1

n

∑1

1 + + + .......... + .1

1 + 2

1

1 + 2 + 3

1

1 + 2 + 3 + ......... + n

n

∑r=1

1

r(r + a)(r + 2)(r + 3)

n

∑r=1

r

(r + 1)!1 × 2 × 3.... n

Page 18: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

108

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum

Watch Free Video Solution on Doubtnut

109

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum

Watch Free Video Solution on Doubtnut

110

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the series

Watch Free Video Solution on Doubtnut

111

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the series

Watch Free Video Solution on Doubtnut

112

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of first 100 terms of the series whose general term is given by

Watch Free Video Solution on Doubtnut

113

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the series terms.

Watch Free Video Solution on Doubtnut

n

∑r=1

r(r + 1)(r + 2)(r + 3).

+ + + ...... +14

1 × 3

24

3 × 5

34

5 × 7

n4

(2n − 1)(2n + 1)

360

∑k=1

( )1

k√k + 1 + (k + 1)√k

+ + + + ∞1

32 + 1

1

42 + 2

1

52 + 3

1

62 + 4

ak = (k2 + 1)k !

+ × 2 + × 22 + × 23 + → n2

1 × 2

5

2 × 3

10

3 × 4

17

4 × 5

Page 19: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

114

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

A sequence of numbers is defined as follows : and for each , then prove that

Watch Free Video Solution on Doubtnut

115

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum of the products of the ten numbers taking two at a time.

Watch Free Video Solution on Doubtnut

116

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum .

Watch Free Video Solution on Doubtnut

117

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Prove that

Watch Free Video Solution on Doubtnut

118

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Prove that .

Watch Free Video Solution on Doubtnut

119

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Find the minimum value of .

Watch Free Video Solution on Doubtnut

A∩ = 1, 2, 3 A1 =1

2n ≥ 2, An = ( )An−1

2n − 3

2nn

∑k=1

Ak < 1, n ≥ 1

±1, ± 2, ± 3, ± 4, and ± 5

n

∑r=0

^ (n + r)Cr

(ab + xy)(ax + by) > 4abxy(a, b, x, y > 0).

b2c2 + c2a2 + a2 + b2 > abc × (a + b + c)(a, b, c > 0)

4sin ^ (2x) + 4cos ^ (2x)

Page 20: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

120

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If then prove that

Watch Free Video Solution on Doubtnut

121

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are distinct positive real numbers such that then prove tha

Watch Free Video Solution on Doubtnut

122

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are positive real number, then find the maximum value of

Watch Free Video Solution on Doubtnut

123

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If Then find the minimum value of the expression

Watch Free Video Solution on Doubtnut

124

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If then find the maximum value of

Watch Free Video Solution on Doubtnut

125

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are positive, then prove that

Watch Free Video Solution on Doubtnut

a + b + c = 1, > − 1 − 1 − 1 > 8.8

27abc

1

a

1

b

1

c

a, b, andc a + b + c = 1, > 8.(1 + a)(1 + b)(1 + c)

(1 − a)(1 − b)(1 − c)

(log)10(x3 + y3) − (log)10(x

2 + y2 − xy) ≤ 2, wherex, y xy.

(log)2(a + b) + (log)2(c + d) ≥ 4. a + b + c + ..

a+a2 + a3 + + an = 1∀a1 > 0, i = 1, 2, 3, , n, a12a2a3a4a5an.

a, b, c a/(b + c) + b/(c + a) + c/(a + b) ≥ 3/2.

Page 21: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

126

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

In a triangle prove that

Watch Free Video Solution on Doubtnut

127

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Prove that where is a positive integer.

Watch Free Video Solution on Doubtnut

128

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Prove that

Watch Free Video Solution on Doubtnut

129

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Find the least value of in an acute angled triangle.

Watch Free Video Solution on Doubtnut

130

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If for then prove that

Watch Free Video Solution on Doubtnut

131

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are positive values, find the greatest value of

Watch Free Video Solution on Doubtnut

ABC a/(a + c) + b/(c + a) + c/(a + b) < 2

2n > 1 + n√2n−1, ∀n > 2 n

[n + 1/2]n > (n !).

secA + secB + secC

S + a1 + a2 + a3 + + an, a1 ∈ R+ i = 1 → n, + + + ≥ , ∀n ≥ 2S

S − a1

S

S − a2

S

S − an

n2

n − 1

yz + zx + xy = 12, wherex, y, z xyz.

Page 22: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

132

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

If such that then show that

Watch Free Video Solution on Doubtnut

133

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

If show that

Watch Free Video Solution on Doubtnut

134

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

Prove that

Watch Free Video Solution on Doubtnut

135

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

Prove that

Watch Free Video Solution on Doubtnut

136

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

If are positive and show that

Watch Free Video Solution on Doubtnut

137

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Prove that

Watch Free Video Solution on Doubtnut

a, b, > 0 a3 + b3 = 2, a + b ≤ 2.

m > 1, n ∈ N 1m + 2m + 22m + 23m + + 2nm−m > n1−m(2n − 1)m

.

+ + > a + b + cb2 + c2

b + c

c2 + a2

c + a

a2 + b2

a + b

> + +a8 + b8 + c8

a3b3c31

a

1

b

1

c

a, b, andc a + b + c = 6, (a + 1/b)2 + (b + 1/c)2 + (c + 1/a)2 ≥ 75/4.

[ ]x+ y+ z

> xxyyzz > [ ]x+ y+ z

(x, y, z > 0)x2 + y2 + z2

x + y + z

x + y + z

3

Page 23: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

138

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Prove that

Watch Free Video Solution on Doubtnut

139

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Find the greatest value of lie in the first quadrant on the line

Watch Free Video Solution on Doubtnut

140

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Find the maximum value of lies between

Watch Free Video Solution on Doubtnut

141

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If then prove that

Watch Free Video Solution on Doubtnut

142

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If is a positive integer, then prove that

Watch Free Video Solution on Doubtnut

143

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Prove that ,where

Watch Free Video Solution on Doubtnut

11 × 22 × 33 × × nn ≤ [(2n + 1)/3]n (n+1) /2

, n ∈ N .

x2y3, wherexandy 3x + 4y = 5.

(7 − x)4(2 + x)5whenx −2and7.

a1, a2, , an > 0, + + + + + > na1

a2

a2

a3

a3

a4

an−1

an

an

a1

a > bandn an − bn > n(ab)(n−1) /2

(a − b).

+ + < + +2

b + c

2

c + a

2

a + b

1

a

1

b

1

ca, b, c > 0.

Page 24: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

144

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Find the minimum value of

Watch Free Video Solution on Doubtnut

145

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If then show that

Watch Free Video Solution on Doubtnut

146

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If are real numbers such that `0 Watch Free Video Solution on Doubtnut

147

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

In , prove that are acute angles.

Watch Free Video Solution on Doubtnut

148

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

In prove that

Watch Free Video Solution on Doubtnut

149

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If prove that `sum_(1lt=i Watch Free Video Solution on Doubtnut

2sinx2cosx.

a2 + b2 + c2 = x2 + y2 + z2 = 1, ax + by + cz < 1.

a, b, c

ΔABC tanA + tanB + tanC ≥ 3√3, whereA,B, C

ABC, cos ec + cos ec + cos ec ≥ 6.A

2

B

2

C

2

ai > 0(i = 1, 2, 3n),

Page 25: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

150

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If is a positive integer then prove that

Watch Free Video Solution on Doubtnut

151

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Prove that the greatest value of is if

Watch Free Video Solution on Doubtnut

152

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Prove that

Watch Free Video Solution on Doubtnut

153

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If the prove that `sqrt(C_1)+sqrt(C_2)+.......sqrt(C_n) lt sqrt(n(2^n­1)) ="">

Watch Free Video Solution on Doubtnut

154

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If prove that

Watch Free Video Solution on Doubtnut

155

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Prove that

Watch Free Video Solution on Doubtnut

n ≥ 1, > 1.3n

2n + n6( )n−12

xy c3 /√2ab. a2x4 + b2y4 = c6.

a4 + b4 + c4 > abc(a + b + c), wherea, b, c > 0.

Cr = ,n !

[r !(n − r)]

a + b = 1, a > 0, (a + )2

+ (b + )2

≥ .1

a

1

b

25

2

[ ]a+ b

> aabb > a+ b

.a2 + b2

a + b

a + b

2

Page 26: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

156

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Prove that

Watch Free Video Solution on Doubtnut

157

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Prove that are distinct and

Watch Free Video Solution on Doubtnut

158

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Given are positive rational numbers such that then prove that

Watch Free Video Solution on Doubtnut

159

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

Find the greatest value of if are positive.

Watch Free Video Solution on Doubtnut

160

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

For prove tht at most one term of the G.P. can be rational.

Watch Free Video Solution on Doubtnut

161

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the terms of the A.P. are all in integers, then find the least composite value of

Watch Free Video Solution on Doubtnut

apbq < ( )p+ q

.ap + bq

p + q

pxq− r + qxr−p + rxp− q > p + q + r, wherep, q, r x ≠ 1.

a, b, c a + b + c = 1, aabbcc + a^ ^ a + acbacb ≤ 1.

x2y3z4 x2 + y2 + z2 = 1, wherex, y, z

a, x, > 0 √a − x, √x, √a + x

√a − x, √x, √a + x wherea, x > 0, a.

Page 27: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

162

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Along a road lie an odd number of stones placed at intervals of 10 metres. These stones have to be assembled around the middle stone. A person cancarry only one stone at a time. A man carried the job with one of the end stones by carrying them in succession. In carrying all the stones he covered adistance of 3 km. Find the number of stones.

Watch Free Video Solution on Doubtnut

163

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the first and the nth terms of a G.P., are respectively, and if is hte product of the first terms prove that

Watch Free Video Solution on Doubtnut

164

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let Find in terms of

Watch Free Video Solution on Doubtnut

165

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If the sum terms of the series then find the value of

Watch Free Video Solution on Doubtnut

166

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Find the sum terms.

Watch Free Video Solution on Doubtnut

167

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are the sums of terms of A.P. whose first terms are and common differences are respectively.

Show that

Watch Free Video Solution on Doubtnut

aandb, P n P 2 = (ab)n.

x = 1 + 3a + 6a2 + 10a3 + , |a| < 1. y = 1 + 4b + 10b2 + 20b3 + , |b| < 1. S + 1 + 3(ab) + 5(ab)2 + xandy.

n + 3( )2

+ 5( )3

+ is36,2n + 1

2n − 1

2n + 1

2n − 1

2n + 1

2n − 1n.

× + × ( )2

+ × ( )2

+ → n3

1 × 2

1

2

4

2 × 3

1

2

5

3 × 4

1

2

S1, S2, S3, Sm n m ' s 1, 2, 3, ,m 1, 3, 5, , (2m − 1)

S1 + S2, + Sm = (mn + 1)mn

2

Page 28: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

168

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If be respectively the sum of n, 2n and 3n terms of a G.P., prove that

Watch Free Video Solution on Doubtnut

169

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

In a sequence of terms, the first terms are n A.P. whose common difference is 2, and the last terms are in G.P. whose

common ratio is 0.5 if the middle terms of the A.P. and LG.P. are equal ,then the middle terms of the sequence is b. c. d.

none of these

Watch Free Video Solution on Doubtnut

170

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Watch Free Video Solution on Doubtnut

171

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let be real numbers such that

then find the value of

Watch Free Video Solution on Doubtnut

172

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If , x (log)_2 5 1­log_52 log_52` d. none of these

Watch Free Video Solution on Doubtnut

173

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If three positive real numbers are in A.P. sich that , then the minimum value of is a. b. c. d.

Watch Free Video Solution on Doubtnut

S1, S2andS3 S1(S3 − S2) = S1(S2 − S1)2

(4n + 1) (2n + 1) (2n + 1)n.2n + 1

22n − 1

n.2n + 1

2n − 1n.2n

∑i=0

∑j=0

∑k=0

1

3i3i3k

a1, a2, .........an √a1 + √a2 − 1 + √a3 − 2 + +√an − (n − 1) = (a1 + a2 + ....... + an) − (n1

2

n − 3

4100

∑i=1

ai

(log)2(5 × 21−x + 1) (log)4(21−x + 1) and 1are ∈ A. P . , then equals b. c.

a, , b, c abc = 4 b 21 / 3 22 / 3 21 / 2 23 / 23

Page 29: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

174

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The maximum sum of the series is b. c. d. none of these

Watch Free Video Solution on Doubtnut

175

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The largest term common to the sequences terms and terms is b. c. d. none of these

Watch Free Video Solution on Doubtnut

176

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sum of terms of an A.P. is the same as teh sum of its terms, then the sum of its terms is b. c. d.

Watch Free Video Solution on Doubtnut

177

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If denotes the sum of terms of A.P., then b. c. d.

Watch Free Video Solution on Doubtnut

178

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

About 150 workers were engaged to finish a piece of work in a certain number of days. Four workers stopped working on the second day, four moreworkers stopped their work on the third day and so on. It took 8 more days to finish the work. Then the number of days in which the work was completedis 29 days b. 24 days c. 25 days d. none of these

Watch Free Video Solution on Doubtnut

179

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

In an A.P. of which is the first term if the sum of the first terms is zero, then the sum of the next terms is a. b. c.

d. none of these

Watch Free Video Solution on Doubtnut

20 + 19 + 18 +1

3

2

3310 300 0320

1, 11, 21, 31, → 100 31, 36, 41, 46, → 100 381 471 281

m n (m + n) mn −mn 1/mn 0

Sn n Sn+1 − 3Sn+2 + 3Sn+1 − Sn = 2S _ n sn+1 3Sn 0

a p qa(p + q)p

q + 1

a(p + q)p

p + 1

−a(p + q)q

p − 1

Page 30: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

180

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If denotes the sum of first terms of an A.P. and , then the value of is 21 b. 15 c.16 d. 19

Watch Free Video Solution on Doubtnut

181

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., then is equal to b. c. d. none of these

Watch Free Video Solution on Doubtnut

182

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The number of terms of an A.P. is even; the sum of the odd terms is 24, and of the even terms is 30, and the last term exceeds the first by 10/2 then thenumber of terms in the series is 8 b. 4 c. 6 d. 10

Watch Free Video Solution on Doubtnut

183

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If and form two arithmetic progressions of the common difference, then are in A.P. if are in A.P. b. are in A.P. c.

are in G.P. d. none of these

Watch Free Video Solution on Doubtnut

184

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Suppose that equals 50 b. 52 c. 54 d. none of these

Watch Free Video Solution on Doubtnut

185

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sum of terms of an A.P. is where then the sum of the squares of these terms is b. c.

d. none of these

Watch Free Video Solution on Doubtnut

Sn n = 31S3n − Sn−1

S2n − S2n−1n

a, b, andc a3 + c3 − 8b3 2abc 6abc 4abc

a, , c1

b, q,

1

p

1

ra, q, c p, b, r , ,

1

p

1

b

1

rp, b, r

F(n + 1) = (2 f or n = 1, 2, 3andF(1) = 2. Then.F(101)

F(n + 1)

2

n cn(n − 1) c ≠ 0, c2n(n + 1)2

c2n(n − 1)(2n − 1)2

3

n(n + 1)(2n + 1)2c2

3

Page 31: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

186

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Consider an A.P. such that then the value of is ­8 b. 5 c. 7 d. 9

Watch Free Video Solution on Doubtnut

187

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If be terms of an A.P. if equals 41/11 b. 7/2 c. 2/7 d. 11/41

Watch Free Video Solution on Doubtnut

188

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If denote the sum of first terms of an A.P. whose first term is is independent of b. c. d.

Watch Free Video Solution on Doubtnut

189

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Three numbers form an increasing G.P. If the middle number is doubled, then the new numbers are in A.P. The common ratio of the G.P. is b. c. d.

Watch Free Video Solution on Doubtnut

190

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are three successive terms of a G.P. with common ratio for which holds is given by `13orr<1` d. none ofthese

Watch Free Video Solution on Doubtnut

191

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let denote the set of values of satisfying the equation . Then, b. c. d.

Watch Free Video Solution on Doubtnut

a1, a2, a3, a3 + a5 + a8 = 11anda4 + a2 + = − 2, a1 + a + 6 + a + 7

a1, a2, a3, = , p ≠ q, thena1 + a2 + + ap

a1 + a2 + + aq

p2

q2a6

a21

Sn n aandSnx /Sx x, thenSp = p3 p2a pa2 a3

2 − √32 + √3 √3 − 2 3 + √2

a1, a2, a3(a1 > 0) r, a + 3 > 4a2 − 3a1

S ⊂ (0, π) x 81 + |cosx| + cos2 x + ∣ cos3x ∣ → ∞ = 43 S = π/3π/3, 2π/3 − π/3, 2π/3 π/3, 2π/3

Page 32: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

192

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If then the sum of the series is b.

c. d.

Watch Free Video Solution on Doubtnut

193

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If term of a G.P. is its term is , then its pth term is b. c. d. none of these

Watch Free Video Solution on Doubtnut

194

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sides of a triangle are in G.P., and its largest angle is twice the smallest, then the common ratio satisfies the inequality `0 Watch Free Video Solution on Doubtnut

195

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The value of is b. c. d. none of these

Watch Free Video Solution on Doubtnut

196

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If then is equal to b. c. d. none of these

Watch Free Video Solution on Doubtnut

197

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P. nad , then b. c. d. none of these

Watch Free Video Solution on Doubtnut

|a| < 1and|b| < 1, 1 + (1 + a)b + (1 + a + a2)b2 + (1 + a + a2 + a3)b3 + ...1

(1 − a)(1 − b)1

(1 − a)(1 − ab)

1

(1 − b)(1 − ab)

1

(1 − a)(1 − b)(1 − ab)

(p + q)th aand (p − q)th bwherea, b ∈ R+ √ a3

b√ b3

a√ab

r

0. 2log√5 + + +14

18

116 4 log 4 log 2

(1 + x)(1 + x2)(1 + x4)(1 + x128) =n

∑r=0

xr n 256 255 254

x, y, z ax = by = cz (log)ba = (log)ac (log)cb = (log)ac (log)ba = (log)cb

Page 33: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

198

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

The geometric mean between ­9 and ­16 is b. c. d. none of these

Watch Free Video Solution on Doubtnut

199

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If denotes the sum to infinity and the sum of terms of the series such that then the least value of is

b. c. d. 11

Watch Free Video Solution on Doubtnut

200

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The first term of an infinite geometric series is The second term and the sum of the series are both positive integers. Then which of the following isnot the possible value of the second term b. c. d. none of these

Watch Free Video Solution on Doubtnut

201

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The number of terms common between the series to terms and to terms is a. b. c. d.none of these

Watch Free Video Solution on Doubtnut

202

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

After striking the floor, a certain ball rebounds (4/5)th of height from which it has fallen. Then the total distance that it travels before coming to rest, if it isgently dropped of a height of 120 m is b. c. d. none of these

Watch Free Video Solution on Doubtnut

203

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The sum of an infinite G.P. is 57 and the sum of their cubes is 9747, then the common ratio of the G.P. is b. c. d. none of these

Watch Free Video Solution on Doubtnut

12 −12 −13

S Sn n 1 + + + + ,1

2

1

4

1

8S − Sn < ,

1

1000n

8 9 10

21.12 14 18

1 + 2 + 4 + 8 + ....... 100 1 + 4 + 7 + 10 + ....... 100 6 4 5

1260m 600m 1080m

1/2 2/3 1/6

Page 34: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

204

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P., then are in a. A.P. b. G.P. c. H.P. d. none of these

Watch Free Video Solution on Doubtnut

205

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Consider the ten numbers If their sum is 18 and the sum of their reciprocals is 6, then the product of these ten numbers is a.b. c. d.

Watch Free Video Solution on Doubtnut

206

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let then (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

207

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let be the nth term of a G.P. of positive numbers. Let , such that , then the common ratio is b.

c. d.

Watch Free Video Solution on Doubtnut

208

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of 20 terms of a series of which every even term is 2 times the term before it, every odd term is 3 times the term before it, the first tem being

unity is b. c. d. none of these

Watch Free Video Solution on Doubtnut

209

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

In a G.P. the first, third, and fifth terms may be considered as the first, fourth, and sixteenth terms of an A.P. Then the fourth term of the A.P., knowing thatits first term is 5, is b. c. d. 20

Watch Free Video Solution on Doubtnut

a2 + b2, ab + bc, andb2 + c2 a, b, c

ar, ar2, ar3, .... . , ar10. 81243 343 324

a = 111....1(55digits), b = 1 + 102 + .... + 104, c = 1 + 105 + 1010 + 1015 + ... + 1050, a = b + c a = bc b = acc = ab

an

100

∑n=1

a2n = αand

100

∑n=1

a2n−1 = β α ≠ β α/β β/α

√α/β √β/α

( )(610 − 1)2

7( )(610 − 1)

3

7( )(610 − 1)

3

5

10 12 16

Page 35: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

210

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the pth, qth, and rth terms of an A.P. are in G.P., then the common ratio of the G.P. is a. b. c. d.

Watch Free Video Solution on Doubtnut

211

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the pth, qth, rth, and sth terms of an A.P. are in G.P., t hen are in a. A.P. b. G.P. c. H.P. d. none of these

Watch Free Video Solution on Doubtnut

212

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P, then is equal to b. c. d.

Watch Free Video Solution on Doubtnut

213

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are digits, then the rational number represented by ...is b. c. d.

Watch Free Video Solution on Doubtnut

214

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of an infinite geometric series is 162 and the sum of its first terms is 160. If the inverse of its common ratio is an integer, then which of thefollowing is not a possible first term? b. c. d. none of these

Watch Free Video Solution on Doubtnut

215

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let Then the number of real number of real values of for which the three unequal numbers are in G.P. is b. c. d. none of these

Watch Free Video Solution on Doubtnut

pr

q2r

p

q + r

p + q

q − r

p − q

p − q, q − r, r − s

a, bc, d (b − c)2 + (c − a)2 + (d − b)2 (a − d)2 (ad)2 (a + d)2 (a/d)2

a, b, c ⊙ cababab cab/990 (99c + ba)/990 (99c + 10a + b)/99(99c + 10a + b)/990

n108 144 160

f(x) = 2x + 1. x f(x), f(2x), f(4x) 1 20

Page 36: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

216

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

Concentric circles of radii are drawn. The interior of the smallest circle is colored red and the angular regions are colored alternatelygreen and red, so that no two adjacent regions are of the same color. Then, the total area of the green regions in sq. cm is equal to b. c.

d.

Watch Free Video Solution on Doubtnut

217

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be a sequence of integers in G.P. in which . Then b. c. d. none of these

Watch Free Video Solution on Doubtnut

218

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., where the distinct numbers are in G.P, then te common ratio of the G.P. is b. c. d.

Watch Free Video Solution on Doubtnut

219

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If denotes the sum of the series the sum of the series in term of is

b. c. d.

Watch Free Video Solution on Doubtnut

220

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are real and are in a. A.P. b. G.P. c. H.P. d. none of these

Watch Free Video Solution on Doubtnut

221

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in H.P., then are in a. A.P b. G.P. c. H.P. d. none of these

Watch Free Video Solution on Doubtnut

1, 2, 3, . . . . , 100cm1000π 5050π

4950π 5151π

tn t4 : t6 = 1: 4andt2 + t5 = 216. t1is 12 14 16

x, 2y, 3z x, y, z 31

32

1

2

Sp 1 + rp + r2p + → ∞andsp 1 − r2pr3p + → ∞, |r| < 1, thenSp + sp S2p

2S2p 0 S2p1

2− S2p

1

2

x, y, z 4x2 + 9y2 + 16z2 − 6xy − 12yz − 8zx = 0, thenx, y, z

a1, a2, , an , , ,a1

a2 + a3 + + an

a2

a1 + a3 + + an

an

a1 + a2 + + an−1

Page 37: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

222

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

If harmonic means between 2 and 3, then a. 20 b.21 c. 40 d. 38

Watch Free Video Solution on Doubtnut

223

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in H.P. and are in a. A.P b. G.P. c. H.P. d. none of these

Watch Free Video Solution on Doubtnut

224

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., the will be in a. A.P b. G.P. c. H.P. d. none of these

Watch Free Video Solution on Doubtnut

225

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are the first three terms of a G.P., then the fourth term is a. 27 b. ­27 c. 13.5 d. ­13.5

Watch Free Video Solution on Doubtnut

226

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of three numbers in G.P. is 14. If one is added to the first and second numbers and 1 is subtracted from the third, the new numbers are in ;A.P.The smallest of them is a. 2 b. 4 c. 6 d. 10

Watch Free Video Solution on Doubtnut

227

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are in A.P. are in H.P., and are in G.P., then is equal to b. c. d.

Watch Free Video Solution on Doubtnut

H1,H2, ,H20are20 + =H1 + 2

H1 − 2

H20 + 3

H20 − 3

a1, a2, a3, an f(k) = (n

∑r=1

ar) − ak, then , , , , ,a1

f(1)

a2

f(2)

a3

f(3)

an

f(n)

a, b, c , ,a

bc

1

c

2

b

x, 2x + 2, and3x + 3

a, b, andc p, q, andr ap, bq, andcr +p

r

r

p−

a

c

c

a+

a

c

c

a+

b

q

q

b−

b

q

q

b

Page 38: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

228

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are in A.P. and are in G.P., then is b.1:3:5 c. d.

Watch Free Video Solution on Doubtnut

229

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let satisfies the equation and Then sum of all possible values of S is a. b. c. d.

Watch Free Video Solution on Doubtnut

230

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let If are the roots of quadratic equation is the roots of quadratic equation , then the

value of is the arithmetic mean of is b. c. d.

Watch Free Video Solution on Doubtnut

231

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

such that are in A.P. and are in H.P., then b. c. d. none of these

Watch Free Video Solution on Doubtnut

232

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If in a progression bears a constant ratio with , then the terms of the progression are in a. A.P b. G.P. c.H.P. d. none of these

Watch Free Video Solution on Doubtnut

233

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P., then are in a. A.P b. G.P. c. H.P. d. none of these

Watch Free Video Solution on Doubtnut

a, b, andc b − a, c − banda a : b : c 1: 2 : 3 2: 3 : 4 1: 2 : 4

a ∈ (0, 1] a2008 − 2a + 1 = 0 S = 1 + a + a2 + .... . + a2007 2010 20092008 2

α, β ∈ R. α, β2 x2 − px + 1 = 0andα2, β x2 − qx + 8 = 0

r ifr

8pandq,

83

283

83

8

83

4

a, b, cx ∈ R+ a, b, andc b, candd ab = cd ac = bd bc = ad

a1, a2, a3, .......... etc ., (ar − ar+1) ar × ar+1

a, b, andc a + b, 2b, andb + c

Page 39: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

234

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are in A.P., are in G.P., and are in H.P. such that , then b. c. d.none of these

Watch Free Video Solution on Doubtnut

235

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

Let Let deonote te arithmetic mean, geometric man, and harmonic mean of 25 and The least value of for which is a. 49 b. 81 c.169 d. 225

Watch Free Video Solution on Doubtnut

236

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The 15th term of the series b. c. d. none of these

Watch Free Video Solution on Doubtnut

237

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

If are in G.P. and respectively, are the arithmetic means between , then the value of is b. c. d. none of

these

Watch Free Video Solution on Doubtnut

238

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

If are in A.P., and are respectively, A.M. and G.M. between are , respectively, the A.M. and G.M. between then b. c. d. none of these

Watch Free Video Solution on Doubtnut

239

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P. with common difference , then the sum of the series is : a. b. c. d.

Watch Free Video Solution on Doubtnut

a, x, andb a, y, andb a, z, b x = 9zanda > 0, b > 0 |y| = 3z x = 3|y| 2y = x + z

n ∈ N , n > 25. A,G,H n. nA,G,H ∈ 25, 26, n

2 + 1 + 1 + + is1

2

7

13

1

9

20

23

10

39

10

21

10

23

a, b, andc x, y, a, b, andb, c +a

x

c

y1 2 1/2

a, bandc pandp' aandbwhileq, q' bandc,p2 + q2 = p ' 2 + q ' 2 pq = p' q' p2 − q2 = p ' 2 − q ' 2

a1, a2, an d ≠ 0 sin d[sec a1sec a2 + (sec)2sec a3 + .... + secan−1(sec)n]cos ecan − cos eca cot an − cot a secan − seca tanan − tana

Page 40: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

240

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of the series up to terms is b. c. d.

Watch Free Video Solution on Doubtnut

241

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of 50 terms of the series is given by b. c. d. none of these

Watch Free Video Solution on Doubtnut

242

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of 50 terms of the series is b. c. d.

Watch Free Video Solution on Doubtnut

243

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If equals b. c. d.

Watch Free Video Solution on Doubtnut

244

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

Coefficient of equal to b. c. d. none of these

Watch Free Video Solution on Doubtnut

245

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

is equal to b. c. d. none of these

Watch Free Video Solution on Doubtnut

a − (a + d) + (a + 2d) − (a + 3d) + (2n + 1) −nd a + 2nd a + nd 2nd

1 + 2(1 + ) + 3(1 + )2

+1

50

1

502500 2550 2450

+ + +3

125

12 + 227

12 + 22 + 32100

17

150

17

200

51

50

17

+ + + → ∞ = , then + + +1

121

221

32π2

6

1

121

321

52π2 /8 π2 /12 π2 /3 π2 /2

x18 ∈ (1 + x + 2x2 + 3x3 + + 18x18)2

995 1005 1235

( lim )n−→∞

n

∑r=1

r

1 × 3 × 5 × 7 × 9 × × (2r + 1)

1

3

3

2

1

2

Page 41: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

246

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

The greatest integer by which is divisible is a. composite number b. odd number c. divisible by 3 d. none of these

Watch Free Video Solution on Doubtnut

247

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If is equal to b. c. d.

Watch Free Video Solution on Doubtnut

248

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Value of is equal to a. b. c. d. none of these

Watch Free Video Solution on Doubtnut

249

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are in H.P. and are in G.P., then b. c. d. none of these

Watch Free Video Solution on Doubtnut

250

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The value of is equal to b. c. d.

Watch Free Video Solution on Doubtnut

251

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If b. c. d.

Watch Free Video Solution on Doubtnut

1 +30

∑r=1

r × r !

n

∑r=1

r4 = I(n), thenn

∑r=1

(2r − 1)4

I(2n) − I(n) I(2n) − 16I(n) I(2n) − 8I(n) I(2n) − 4I(n)

(1 + )(1 + )(1 + )(1 + )....... . ∞1

3

1

321

341

383

6

5

3

2

x1, x2, x20 x1, 2, x20

19

∑r=1

xrxr+1 = 76 80 84

n

∑r=0

(a + r + ar)( − a)r ( − 1)n[(n + 1)an+1 − a] ( − 1)n(n + 1)an+1 ( − 1)n(n + 2)an+1

2( − 1)n

nan

2

bi = 1 − ai, na =n

∑i=1

ai, nb =n

∑i=1

bi, thenn

∑i=1

ai, bi +n

∑i=1

(ai − a)2= ab nab (n + 1)ab nab

Page 42: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

252

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of series to infinite terms, if is b. c. d.

Watch Free Video Solution on Doubtnut

253

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are in A.P., then is equal to b. c.

d. none of these

Watch Free Video Solution on Doubtnut

254

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The sum of up to 100 terms, where is b. c. d.

Watch Free Video Solution on Doubtnut

255

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let . Then is equal to b. c. d. none of these

Watch Free Video Solution on Doubtnut

256

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If , then the value of is b. c. d.

Watch Free Video Solution on Doubtnut

257

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sum to infinity of the series is 9/4, then value of is (a) b. c. d. none of these

Watch Free Video Solution on Doubtnut

+ + +x

1 − x2

x2

1 − x4

x4

1 − x8|x| < 1,

x

1 − x

1

1 − x

1 + x

1 − x1

a1, a2, a3, , a2n+1 + + +a2n+1 − a1

a2n+1 + a1

a2n − a2

a2n + a2

an+2 − an

an+2 + an×

n(n + 1)

2

a2 − a1

an+1

n(n + 1)

2(n + 1)(a2 − a1)

i − 2 − 3i + 4 i = √−1 50(1 − i) 25i 25(1 + i) 100(1 − i)

S = + + + up → ∞4

19

44

192444

193s 40/9 38/81 36/171

Hn = 1 + + + .1

2

1

nSn = 1 + + + +

3

2

5

3

99

50H50 + 50 100 − H50 49 + H50 H50 + 100

1 + 2r + 3r2 + 4r3 + r 1/2 1/3 1/4

Page 43: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

258

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum o f series is b. c. d.

Watch Free Video Solution on Doubtnut

259

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

If A.M., G.M., and H.M. of the first and last terms of the series of are the terms of the series itself, then the value of `ni s(100 Watch Free Video Solution on Doubtnut

260

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum terms is b. c. d. none of these

Watch Free Video Solution on Doubtnut

261

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

In a sequence of terms, the first terms are n A.P. whose common difference is 2, and the last terms are in G.P. whose

common ratio is 0.5 if the middle terms of the A.P. and LG.P. are equal ,then the middle terms of the sequence is a. b. c. d.

none of these

Watch Free Video Solution on Doubtnut

262

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

The coefficient of in the product b. c. d. none of these

Watch Free Video Solution on Doubtnut

263

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of 20 terms of the series whose rth term s given by k is b. c. d. none of these

Watch Free Video Solution on Doubtnut

1 + + + + ∞4

5

7

5210

537/16 5/16 104/64 35/16

100, 101, 102, ...n − 1, n

1 + 3 + 7 + 15 + 31 + ... → 100 2100 − 102b 299 − 101 2101 − 102

(4n + 1) (2n + 1) (2n + 1)n.2n + 1

22n − 1

n.2n + 1

2n − 1n.2n

x49 (x − 1)(x − 3)(x + 99)is −992 1 −2500

T (n) = ( − 1)n n

2 + n + 1

n !

20

19!− 1

21

20!

21

20!

Page 44: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

264

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Consider the sequence 1,2,2,4,4,4,8,8,8,8,8,8,8,8,... Then 1025th terms will be b. c. d.

Watch Free Video Solution on Doubtnut

265

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If for then b. c. d.

Watch Free Video Solution on Doubtnut

266

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The sum of to is b. c. d. none of these

Watch Free Video Solution on Doubtnut

267

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The value of then the value of equals a. b. c. d.

Watch Free Video Solution on Doubtnut

268

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If equals b. c. d. 2001

Watch Free Video Solution on Doubtnut

269

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If denotes the nth term of the series b. c. d.

Watch Free Video Solution on Doubtnut

29 211 210 212

tn =1

4(n + 2)(n + 3)n = 1, 2, 3, , + + + + =

1

t1

1

t2

1

t3

1

t2003

4006

3006

3006

3007

4006

3008

4006

3009

0. 2 + 0004 + 0. 00006 + 0. 0000008 + ... ∞200

891

2000

9801

1000

9801

n

∑i=1

i

∑j=1

j

∑k=1

1 = 220, n 11 12 10 9

12 + 22 + 32 + + 20032 = (2003)(4007)(334)and(1)(2003) + (2)(2002) + (3)(2001) + + (2003)(1) = (2003)(334)(x), thenx2005 2004 2003

tn 2 + 3 + 6 + 11 + 18 + ...thent50 492 − 1 492 502 + 1 492 + 2

Page 45: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

270

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The positive integer for which is a. b. c. d.

Watch Free Video Solution on Doubtnut

271

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If , then value of is b. c. d.

Watch Free Video Solution on Doubtnut

272

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

The coefficient of in the polynomial is b. c. d. none of these

Watch Free Video Solution on Doubtnut

273

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If is equal to b. c. d. none of these

Watch Free Video Solution on Doubtnut

274

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If , then is equal to b. c. d. none of these

Watch Free Video Solution on Doubtnut

275

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If is divisible by are in a. A.P. b. G.P. c. H.P. d. none of these

Watch Free Video Solution on Doubtnut

n 2 × 22 + 3 × 23 + 4 × 24 + ...... + n × 2n = 2n+10 510 511 512 513

1 − + − + − + =1

3

1

5

1

7

1

9

1

11

π

4+ + +

1

1 × 3

1

5 × 7

1

9 × 11π/8 π/6 π/4 π/36

x19 (x − 1)(x − 2)(x − 22)(x − 219) 220 − 219 1 − 220 220

bn+1 = f or n ≥ 1andb1 = b3, then2001

∑r=1

br20011

1 − bn2001 −2001 0

(12 − t1) + (22 − t2) + + (n2 − tn) + =n(n2 − 1)

3tn n2 2n n2 − 2n

ax3 + bx2 + cx + d ax2 + c, thena, b, c, d

Page 46: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

276

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If where each set of parentheses contains the sum of consecutive odd integers asshown, the smallest possible value of is b. c. d.

Watch Free Video Solution on Doubtnut

277

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

In a geometric series, the first term is and common ratio is If denotes the sum of the terms and

equals b. c. d.

Watch Free Video Solution on Doubtnut

278

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The line meets X­axis at A and Y­axis at B,P is the mid­point of is the foot ofperpendicular from P to , is that of , from , is that of from , is that of , from is that of , from OA and so on. If denotes the nth foot of the perpendicular on OA,

then find .

Watch Free Video Solution on Doubtnut

279

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

If , then the value of a b. c. d.

Watch Free Video Solution on Doubtnut

280

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

is a right­angled triangle in which and If points is divided in equal parts and are line segments parallel to are on then the sum of the lengths of is

b. c. d. none of these

Watch Free Video Solution on Doubtnut

281

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let be the rth term and sum up to rth term of a series, respectively. If for an odd number ( being

even)is b. c. d.

Watch Free Video Solution on Doubtnut

(1 + 3 + 5 + + p) + (1 + 3 + 5 + + q) = (1 + 3 + 5 + + r)p + q + r(wherep > 6) 12 21 45 54

a r. Sn Un =n

∑n=1

Sn, thenrSn + (1 + = − r)Un

0 n na nar

x + y = 1 AB, P1 OA,M1 P1OP ; P2 M1 OA,M2 P2 OP ; P3 M2 Pn

OPn

(1 − p)(1 + 3x + 9x2 + 27x3 + 81x4 + 243x5) = 1 − p6, p ≠ 1 isp

x

1

33

1

22

ABC ∠B = 900 BC = a. n L1, L2, , LnonAB n + 1L1M1, L2M2, , LnMn BCandM1,M2, ,Mn AC, L1M1, L2M2, , LnMn

a(n + 1)

2

a(n − 1)

2

an

2

TrandSr n, Sn = nandTn = , thenTmTn − 1

n2m

2

1 + m2

2m2

1 + m2

(m + 1)2

2 + (m + 1)22(m + 1)2

1 + (m + 1)2

Page 47: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

282

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

ABCD is a square of length a, , a > 1. Let be points on BC such that and be

points on CD such that . Then is equal to :

Watch Free Video Solution on Doubtnut

283

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P. and are in H.P., then b. c. d.

Watch Free Video Solution on Doubtnut

284

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are distinct prime numbers, then may be in A.P. but not in G.P. may be in G.P. but not in A.P. can neitherbe in A.P. nor in G.P. none of these

Watch Free Video Solution on Doubtnut

285

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

For the series, +... 7th term is 16 7th term is 18

Sum of first 10 terms is Sum of first 10 terms is

Watch Free Video Solution on Doubtnut

286

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If sum of an infinite G.P. then value of is a. 3 b. 3/2 c. 3 d. 9/2

Watch Free Video Solution on Doubtnut

287

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If then are in A.P. is an integer

Watch Free Video Solution on Doubtnut

a ∈ N L1, L2, L3... BL1 = L1L2 = L2L3 = .... 1 M1,M2,M3, ....

CM1 = M1M2 = M2M3 = ... = 1a−1

∑n=1

((ALn)2 + (LnMn)

2)

x, y, andz x + 3 + , y + 3, andz + 3 y = 2 y = 3 y = 1 y = 0

x, y, andz x, y, andz x, y, andz x, y, andz

S = 1 + (1 + 2)2+ (1 + 2 + 3)

2+ (1 + 2 + 3 + 4)

21

(1 + 3)

1

(1 + 3 + 5)

1

(1 + 3 + 5 + 7)505

4

45

4

p, 1, 1/p, 1/p2, is9/2 p

n

∑r=1

r(r + 1)(2r + 3) = an4 + bn3 + cn2 + dn + e, a − b = d − c e = 0 a, b − 2/3, c − 1 (b + d)/a

Page 48: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

288

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The terms of an infinitely decreasing G.P. in which all the terms are positive, the first term is 4, and the difference between the third and fifth terms is , then b. c. d. none of these

Watch Free Video Solution on Doubtnut

289

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The consecutive digits of a three digit number are in G.P. If middle digit is increased by 2, then they form an A.P. If 792 is subtracted from this, then we getthe number constituting of same three digits but in reverse order. Then number is divisible by a. 7 b. 49 c. 19 d. noneof these

Watch Free Video Solution on Doubtnut

290

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If b. c. d.

Watch Free Video Solution on Doubtnut

291

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Given that are in A.P. and are in H.P. Then G.M. of is 3 One

possible value of is 11 A.M. of is 6 Greatest value of is 8

Watch Free Video Solution on Doubtnut

292

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be in G.P. such that Then common ratio of G.P. can be b. c. d.

Watch Free Video Solution on Doubtnut

293

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

terms is equal to b. c. less than d. less than

Watch Free Video Solution on Doubtnut

32/81 r = 1/3 r = 2√2/3 S∞ = 6

Sn = 12 − 22 + 32 − 42 + 52 − 62 + , then S40 = − 820 S2n > S2n+2 S51 = 1326 S2n+1 > S2n−1

x + y + z = 15whena, x, y, z, b + + + = whena, x, y, z, b1

x

1

y

1

z

5

3aandb

a + 2b aandb a − b

a1, a2, a3, , an 3a1 + 7a2 + 3a3 − 4a5 = 0. 23

2

5

2−

1

2

+ + + n1

√2 + √5

1

√5 + √8

1

√8 + √11

√3n + 2 − √2

3

n

√2 + 3n + √2n √

n

3

Page 49: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

294

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in H.P., then th value of is b. c. d.

Watch Free Video Solution on Doubtnut

295

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If is a polynomial in can be b. c. d.

Watch Free Video Solution on Doubtnut

296

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

For an increasing A.P. and then which of the following is/are true? a. b. c. d.

Watch Free Video Solution on Doubtnut

297

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If , the value of the positive integer for which divides is/are b. c. d.

Watch Free Video Solution on Doubtnut

298

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., then which of the following is/are true? pth, qth, and rth terms of A.P. are in A.P. pth, qth, rth terms of G.P. are in G.P. pth, qth, rthterms of H.P., are in H.P. none of these

Watch Free Video Solution on Doubtnut

299

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If , then least value of greatest value of least value of greatest value of does not exists

Watch Free Video Solution on Doubtnut

a, b, andc(ac + ab − bc)(ab + bc − ac)

(abc)2

(a + c)(3a − c)

4a2c2−

2

bc

1

b2−

2

bc

1

a2

(a − c)(3a + c)

4a2c2

p(x) =1 + x2 + x4 + + x

1 + x + x2 + + xn−1 ^ (2n − 2)x, the ∩ 5 10 20 17

a1, a2, an if a1 = a2 + a3 + a5 = − 12 a1a3a5 = 80, a1 = − 10a2 = − 1 a3 = − 4 a5 = + 2

n > 1 m nm + 1 a = 1 + n + n2 +..+ n63 8 16 32 64

p, q, andr

1 + 2x + 3x2 + 4x3 + ∞ ≥ 4 ξs1/2 ξs4

3ξs2/3 x

Page 50: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

300

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let Then, a. b. c. d.

Watch Free Video Solution on Doubtnut

301

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sum of terms of an A.P. is given by are independent of (a) (b) common difference of A.P.must be (c) common difference of A.P. must be (d) first term of A.P. is

Watch Free Video Solution on Doubtnut

302

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in H.P. b. are in A.P. c. are in G.P. d.

Watch Free Video Solution on Doubtnut

303

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The next term of the G.P. is b. c. d.

Watch Free Video Solution on Doubtnut

304

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let be squares such that for each the length of a side of equals the length of a diagonal of If the length of a side of then for which of the following value of is the area of less than 1 sq. cm? a. 5 b. 7 c. 9 d. 10

Watch Free Video Solution on Doubtnut

305

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If then A. are in H.P. B. are in A.P. C. D.

Watch Free Video Solution on Doubtnut

E = + + +1

121

221

32E < 3 E > 3/2 E > 2 E < 2

n Sn = a + bn + cn2, wherea, b, c n, then a = 02b 2c b + c

x2 + 9y2 + 25z2 = xyz( + + ), then15

x

5

y

3

zx, y, andz , ,

1

x

1

y

1

zx, y, z + = =

1

a

1

d

1

b

1

c

x, x2 + 2, andx3 + 10729

166 0 54

S1, S2, n ≥ 1, Sn Sn+1.S1is10cm, n Sn

+ = + ,1

b − a

1

b − c

1

a

1

ca, b, andc a, b, andc b = a + c 3a = b + c

Page 51: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

306

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P. and respectively, be arithmetic means between b. c. d.

Watch Free Video Solution on Doubtnut

307

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Consider a sequence for all terms of the sequence being distinct. Given that are positive

integers and then the possible value can be a. 162 b. 64 c. 32 d. 2

Watch Free Video Solution on Doubtnut

308

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Which of the following can be terms (not necessarily consecutive) of any A.P.? a. 1,6,19 b. c. d.

Watch Free Video Solution on Doubtnut

309

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The numbers 1, 4, 16 can be three terms (not necessarily consecutive) of no A.P. only on G.P. infinite number o A.P.’s infinite number of G.P.’s

Watch Free Video Solution on Doubtnut

310

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Each question has four choices a,b,c and d out of which only one is correct. Each question contains Statement 1 and Statement 2. Make your answer as:If both the statements are true and Statement 2 is the correct explanation of statement 1. If both the statements are True but Statement 2 is not the

correct explanation of Statement 1. If Statement 1 is True and Statement 2 is False. If Statement 1 is False and Statement 2 is True. Statement 1:

is a root of Statement 2: For any

Watch Free Video Solution on Doubtnut

311

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

if a G.P (p+q)th term = m and (p­q) th term = n , then find its p th term

Watch Free Video Solution on Doubtnut

a, b, andc xandy, a, b, andb, c, then + = 2a

x

c

y+ =

a

x

c

y

c

a+ =

1

x

1

y

2

b

+ =1

x

1y

2

ac

anwitha1 = 2andan =an − 12

an−2n ≥ 3, a1anda5

a5 ≤ 162 (s)ofa5

√2, √50, √98 log 2, log 16, log 128 √2, √3, √7

sinπ

188x3 − 6x + 1 = 0 θ ∈ R, sin 3θ = 3 sin θ − 4 sin3 θ

Page 52: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

312

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in H.P. b. are in A.P. c. are in G.P. d.

Watch Free Video Solution on Doubtnut

313

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the roots of are in harmonic oprogresion, then eqauls _________.

Watch Free Video Solution on Doubtnut

314

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The difference between the sum of the first terms of the series and the sum of the first terms of The value of is __________.

Watch Free Video Solution on Doubtnut

315

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

The value of the is equal to_________.

Watch Free Video Solution on Doubtnut

316

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let are in G.P. with Then the value of equals____________.

Watch Free Video Solution on Doubtnut

317

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let , then equals ___________.

Watch Free Video Solution on Doubtnut

x2 + 9y2 + 25z2 = xyz( + + ), then15

2

5

y

3

zx, y, andz , ,

1

x

1

y

1

zx, y, z + = =

1

a

1

d

1

b

1

c

10x3 − nx2 − 54x − 27 = 0 n

k 13 + 23 + 33 + + n3 k 1 + 2 + 3 + + nis1980.k

∑n=0

2n + 3

3n

a1, a2, a3, , a101 a101 = 25and201

∑i=1

a1 = 625.201

∑i=1

1

a1

S =9999

∑n=1

1

(√n + √n + 1)(n4 + n + 14)S

Page 53: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

318

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The 5th and 8th terms of a geometric sequence of real numbers are 7! And 8! Respectively. If the sum to first tems of the G.P. is 2205, then equals_______.

Watch Free Video Solution on Doubtnut

319

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be four distinct real numbers in A.P. Then half of the smallest positive valueof satisfying is __________.

Watch Free Video Solution on Doubtnut

320

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The number of positive integral ordered pairs of such that are in harmonic progression is _________.

Watch Free Video Solution on Doubtnut

321

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let let be in A.P. and are in G.P., then the value of is _______.

Watch Free Video Solution on Doubtnut

322

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The coefficient of the quadratic equation are consecutive terms of a positively valued, increasing arithmetic sequence.Then the least integral value of such that the equation has real solutions is __________.

Watch Free Video Solution on Doubtnut

323

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be two infinite series of positive numbers with the same first term. The sum of the firstseries is and the sum of the second series Then the value of is ________.

Watch Free Video Solution on Doubtnut

n n

a, b, c, d k

2(a − b) + k(b − c)2 + (c − a)3 = 2(a − d) + (b − d)2 + (c − d)3

(a, b) 6, a, b

a, b > 0, 5a − b, 2a + b, a + 2b (b + 1)2, ab + 1, (a − 1)2 (a−1 + b−1)

ax2 + (a + d)x + (a + 2d) = 0d/a

a + ar1 + ar12 + + ∞anda + ar2 + ar22 + + ∞r1 r2. (r1 + r2)

Page 54: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

324

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If he equation has three real roots in G.P., then has the value equal to _____.

Watch Free Video Solution on Doubtnut

325

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be a geometric sequence. Define as the product of the first terms. Then the value of is _________.

Watch Free Video Solution on Doubtnut

326

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The terms from an arithmetic sequence whose sum s 18. The terms in that order, form a geometric sequence. Then theabsolute value of the sum of all possible common difference of the A.P. is ________.

Watch Free Video Solution on Doubtnut

327

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Given are in A.P. are in G.P. and are in H.P. If then the sum of all possible value of is ________.

Watch Free Video Solution on Doubtnut

328

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let the sum of first three terms of G.P. with real terms be 13/12 and their product is ­1. If the absolute value of the sum of their infinite terms is then thevalue of is ______.

Watch Free Video Solution on Doubtnut

329

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let denote sum of the series Then the value of is __________.

Watch Free Video Solution on Doubtnut

x3 + ax2 + bx + 216 = 0 b/a

an = 16, 4, 1, Pn n

∑n=1

Pn1

4

1n

a1, a2, a3 a1 + 1, a2, a3, + 2,

a, b, c b, c, d c, d, e a = 2ad ≠ = 18, c

S,7S

S + + + + ∞3

234

24.3

5

26.3

6

27.5S −1

Page 55: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

330

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The first term of an arithmetic progression is and the sum of the first nine terms equal to . The first and the ninth term of a geometric progressioncoincide with the first and the ninth term of the arithmetic progression. Find the seventh term of the geometric progression.

Watch Free Video Solution on Doubtnut

331

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

The harmonic mean of two numbers is 4. Their arithmetic mean and the geometric mean satisfy the relation Find two numbers.

Watch Free Video Solution on Doubtnut

332

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The interior angles of a polygon are in arithmetic progression. The smallest angle is and the common difference is Find the number of sides ofthe polygon

Watch Free Video Solution on Doubtnut

333

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., where for all , show that

Watch Free Video Solution on Doubtnut

334

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

How many geometric progressions are possible containing 27, 8 and 12 as three of its/their terms

Watch Free Video Solution on Doubtnut

335

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

9. Find three numbers a,b,c between 2 & 18 such that; (G) their sum is 25 (ii) the numbers 2,a,b are consecutive terms of an AP & (ii) the numbers b,c, 18are consecutive terms of a G.P.

Watch Free Video Solution on Doubtnut

1 369

A G 2A + G2 = 27.

120 ∘ 5 ∘

a1, a2, a3, , an ai > 0 i + + + = .1

√a1 + √a2

1

√a1 + √a3

1

√an−1 + √an

n − 1

√a1 + √an

Page 56: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

336

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The sum of the first three terms of a strictly increasing G.P. is and sum of their squares is

Watch Free Video Solution on Doubtnut

337

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in arithmetic progression, determine the value of

Watch Free Video Solution on Doubtnut

338

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

If p is the first of the n arithmetic means between two numbers and q be the first on n harmonic means between the same numbers. Then, show that q

does not lie between p and

Watch Free Video Solution on Doubtnut

339

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are the sums of infinite geometric series whose first terms are and whose common ratio

respectively, then find the value of .

Watch Free Video Solution on Doubtnut

340

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

The real numbers satisfying the equation ar ein A.P. Find the intervals in which lie.

Watch Free Video Solution on Doubtnut

341

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

Let be real numbers in If satisfy the system of equations then

show that the roots of the equation and 20x^2+10(a­d)^2 x­9=0` are

reciprocals of each other.

Watch Free Video Solution on Doubtnut

αs s2

(log)32, (log)3(2x − 5)and(log)3(2

x − )7

2x.

( )2

p.n + 1

n − 1

S1, S2, S3, .........Sn, ....... . 1, 2, 3............n, .............

, , , ....... . , , ....1

2

1

3

1

4

1

n + 1

2n−1

∑r=1

S21

x1, x2, x3 x3 − x2 + bx + γ = 0 βandγ

a, b, c, d G. P . u, v, w u + 2y + 3w = 6, 4u + 5v + 6w = 12 and 6u + 9v = 4

( + )x2 + [(b − c)2 + (c − a)2 + (d − b)2]x + u + v + w = 01

u

1

v

+

w

Page 57: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

342

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

The fourth power of common difference of an arithmetic progression with integer entries is added to the product of any four consecutive terms of it. Provethat the resulting sum is the square of an integer.

Watch Free Video Solution on Doubtnut

343

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

.Let be positive real numbers in geometric progression. For each n, let , be respectively the arithmetic mean, geometric mean& harmonic mean of . Find an expression ,for the geometric mean of in terms of

.

Watch Free Video Solution on Doubtnut

344

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be positive real numbers. If be are in arithmetic progression are in geometric progression, and are in

harmonic progression, show that

Watch Free Video Solution on Doubtnut

345

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P. and are in H.P., then prove that either form a G.P.

Watch Free Video Solution on Doubtnut

346

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If and , then find the minimum natural number n, such that

Watch Free Video Solution on Doubtnut

347

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If are pth, qth, and rth terms, respectively, of an A.P. nd also of a G.P., then is equal to a. b. c. d. none of these

Watch Free Video Solution on Doubtnut

a1, a2, ............ AnGn,Hn

a1, a2.......... an G1,G2, ....... .Gn

A1,A2, ....... . ,An,H1,H2, ....... . ,Hn

a, b aA1,A2, b a,G1,G2, b a,H1,H2, b

=G1G2

H1H2

A1 + A2

H1 + H2

a, b, c a2, b2, c2 a = b = c or a, b, −c

2

an = − ( )2

+ ( )3

+ ...( − 1)n−1( )n

3

4

3

4

3

4

3

4bn = 1 − an bn > an

x, y, andz xy− zyz−xzx− y xyz 0 1

Page 58: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

348

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

The third term of a geometric progression is 4. The production of the first five terms is b. c. d. none of these

Watch Free Video Solution on Doubtnut

349

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

In triangle ABC medians AD and CE are drawn, if AD=5, and , then the area of triangle ABC is equal to a. b. c.

d.

Watch Free Video Solution on Doubtnut

350

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P., then the equations have a common root if are in a. A.P. b. G.P. c. H.P.

d. none of these

Watch Free Video Solution on Doubtnut

351

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Sum of the first terms of the series is equal to b. c. d.

Watch Free Video Solution on Doubtnut

352

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Find the sum b. c. d. none of these

Watch Free Video Solution on Doubtnut

353

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in A.P., then (a) are in A.P. (b) are in A.P. (c) are in G.P. d. (d) are in H.P.

Watch Free Video Solution on Doubtnut

43 45 44

∠DAC =π

8∠ACE =

π

4

25

8

25

3

25

1810

3

a, b, andc ax2 + 2bx + c = 0anddx2 + 2ex + f = 0 , ,d

c

e

b

f

c

n + + + +1

2

3

4

7

8

15

162n − n − 1 1 − 2−n n + 2−n − 1 2n + 1

(x + 2)n−1 + (x + 2)n−2(x + 1)+ (x + 2)n−3(x + 1)2 + + (x + 1)n−1 (x + 2)n−2 − (x + 1)n (x + 2)n−2 − (x + 1)n−1

(x + 2)n− (x + 1)

n

ln(a + c), ln(a − c)andln(a − 2b + c) a, b, c a2, b2, c2, a, b, c a, b, c

Page 59: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

354

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be in A.P. and be in H.P. If is b. c. d.

Watch Free Video Solution on Doubtnut

355

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Properties Of A.M. And G.M. And H.M.

The harmonic mean of the roots of the equation is b. c. d.

Watch Free Video Solution on Doubtnut

356

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let the positive numbers be in the A.P. Then are a. not in A.P. /G.P./H.P. b. in A.P. c. in G.P. d. in H.P.

Watch Free Video Solution on Doubtnut

357

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Consider an infinite geometric series with first term and common ratio If its sum is 4 and the second term is 3/4, then b.

c. d.

Watch Free Video Solution on Doubtnut

358

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be the roots of be the root of If are in G.P., then the integral values of , respectively, are b. c. d.

Watch Free Video Solution on Doubtnut

359

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If the sum of the first terms of the A.P. 2, 5, 8, ..., is equal to the sum of the first terms of A.P. 57, 59, 61, ..., then equals b. c. d.

Watch Free Video Solution on Doubtnut

a1, a2, , a10 h1, h2, h10 a1 = h1 = 2anda10 = h10 = 3, thena4h7 2 3 5 6

(5 + √2)x2 − (4 + √5)x + 8 + 2√5 = 0 2 4 6 8

a, b, cadnd abc, abd, acd, andbcd

a r. a = , r =4

7

3

7

a = 2, r =3

8a = , r =

3

2

1

2a = 3, r =

1

4

αandβ x2 − x + p = 0andγandδ x2 − 4x + q = 0. α, β, andγ, δ pandq−2, − 32 −2, 3 −6, 3 −6, − 32

2n n n 10 12 11 13

Page 60: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

360

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

An infinite G.P. has first term as and sum 5, then

Watch Free Video Solution on Doubtnut

361

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

in the quadratic , and , , , are in G.P , where are the roots of , then

Watch Free Video Solution on Doubtnut

362

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be in harmonic progression with The least positive integer for which a. b. c. d.

Watch Free Video Solution on Doubtnut

363

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If first and terms of an AP, GP. and HP. are equal and their nth terms are a, b, c respectively, then (a) a=b=c (b)a+c=b (c) a>b>c and (d) none of these

Watch Free Video Solution on Doubtnut

364

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

If `x=sum_(n=0)^oocos^(2n)theta,y=sum_(n=0)^oosin^(2n)varphi,z=sum_(n=0)^oocos^(2n)thetasin^(2n)varphi,w h e r e0 Watch Free Video Solution on Doubtnut

365

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Q. Let n be an add integer if sin ntheta­sum_(r=0)^n(b_r)sin^rtheta, for every value of theta then ­­­

Watch Free Video Solution on Doubtnut

a

ax2 + bx + c = 0 D = b2 − 4ac α + β α2 + β2 α3 + β3 α, β ax2 + bx + c

a1, a2, a3, ... a1 = 5anda20 = 25. n an < 0 22 23 24 25

(2n − 1)thac − b2 = 0

Page 61: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

366

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be the rth term of an A.P., for If for some positive integers we have equals a. b.

c. d.

Watch Free Video Solution on Doubtnut

367

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

If are in G.P., then are in b. c. d. none of these

Watch Free Video Solution on Doubtnut

368

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

For a positive integer let Then b. c. d.

Watch Free Video Solution on Doubtnut

369

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let Then can take value (s) b. c. d.

Watch Free Video Solution on Doubtnut

370

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let denotes thesum of the infinite geometric series whose first term s and the common ratio is , then the value of

is _______.

Watch Free Video Solution on Doubtnut

371

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Le be real numbers satisfying for If

then the value of is equals to _______.

Watch Free Video Solution on Doubtnut

Tr r = 1, 2, 3, .... . m, n, Tm = andTn = , thenTmn1

n

1

m

1

mn

+1

m

1

n1 0

x > 1, y > 1, andz > 1 , and1

1 + lnx

1

1 + lny

1

1 + lnzA

.P . H

.P . G

.P .

n a(n) = 1 + + + + .1

2

1

3

1

4

1

(2n) − 1a(100) ≤ 100 a(100)

.> 100 a(200) ≤ 100 a(200) ≤ 100

Sn =4n

∑k=1

( − 1) k2.k(k + 1)

2Sn 1056 1088 1120 1332

Sk, k = 1, 2, , 100,k − 1

k !

1

k

+100

∑k=1

(k2 − 3k + 1)Sk

1002

100!

a1, a2, a3, , a11 a1 = 15, 27 − 2a2 > 0andak = 2ak−1 − ak−2 k = 3, 4, , 11.

= 90,a12 + a22 + ... + a112

11

a1 + a2 + + a11

11

Page 62: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

372

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Let be an arithmetic progression with For any integer with let If

does not depend on then is__________.

Watch Free Video Solution on Doubtnut

373

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

A pack contains cards numbered from 1 to . Two consecutive numbered cards are removed from the pack and the sum of the numbers on theremaining cards is 1224. If the smaller of het numbers on the removed cards is then ____________.

Watch Free Video Solution on Doubtnut

374

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous Series

Let a,b ,c be positive integers such that is an integer. If a,b,c are in GP and the arithmetic mean of a,b,c, is b+2 then the value of is

Watch Free Video Solution on Doubtnut

375

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Progression

Suppose that all the terms of an arithmetic progression (A.P.) are natural numbers. If the ratio of the sum of the first seven terms to the sum of the firsteleven terms is 6: 11 and the seventh term lies in between 130 and 140, then the common difference of this A.P. is

Watch Free Video Solution on Doubtnut

376

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If (a and b are positive real numbers) has 3 real roots, then prove that

Watch Free Video Solution on Doubtnut

377

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

In internal angle bisector AI,BI and CI are produced to meet opposite sides in respectively. Prove that the maximum value of

is

Watch Free Video Solution on Doubtnut

a1, a2, a3, , a100 a1 = 3andsp =p

∑i=1

ai, 1 ≤ p ≤ 100. n 1 ≤ n ≤ 20, m = 5n.

Sm

Sn

n, a2

n nk, k − 20 =

b

a

a2 + a − 14

a + 1

2x3 + ax2 + bx + 4 = 0 a + b ≥ 6(2 + 4 )13

13

ABC A' ,B' , C'

AI × BI × CI

AA' × BB' × C'

8

27

Page 63: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

378

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

In how many parts an integer should be dissected so that the product of the parts is maximized.

Watch Free Video Solution on Doubtnut

379

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

The minimum value of for positive real numbers is (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

380

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

A rod of fixed length slides along the coordinates axes, If it meets the axes at , then the minimum value of

(a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

381

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

The least value of is 54 when . Is applicable for 54 when . Isapplicable for and18 is added further 78 when none

Watch Free Video Solution on Doubtnut

382

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are in A.P. then the minimum value of is (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

383

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If , then the least value of is (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

N ≥ 5

x4 + y4 + z2

xyzx, y, z √2 2√2 4√2 8√2

k A(a, 0)andB(0, b)

(a + )2

+ (b + )2

1

a

1

b0 8 k2 + 4 +

4

k2k2 + 4 +

4

k2

6 tan2 φ + 54 cot2 φ + 18 (I) A.M. ≥ GM 6 tan2 φ, 54 cot2 φ, 18 (II) A.M. ≥ GM

6 tan2 φ, 54 cot2 φ (III) tan2 φ = cot2 φ (IV )

ab2c3, a2b3c4, a3b4c5 (a, b, c > 0), a + b + c 1 3 5 9

y = 3x−1 + 3−x−1 y 2 6 2/3 3/2

Page 64: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

384

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Minimum value of (for real positive numbers is (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

385

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

If the product of positive numbers is , then their sum is (a) positive integer (b). divisible by (c)equal to (d)never less than

Watch Free Video Solution on Doubtnut

386

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

The minimum value of when , is

Watch Free Video Solution on Doubtnut

387

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are the three positive roots of the equation then the minimum value of equals

Watch Free Video Solution on Doubtnut

388

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If positive numbers are in H.P., then equation has (a)both roots positive (b)both roots negative(c)one positive and one negative root (d)both roots imaginary

Watch Free Video Solution on Doubtnut

389

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

For to have real solutions, the range of is

Watch Free Video Solution on Doubtnut

(b + c)/a + (c + a)/b + (a + b)/c a, b, c) 1 2 4 6

n nn a n n + 1/n n2

P = bcx + cay + abz, xyz = abc

l,m, n x3 − ax2 + bx − 48 = 0, (1/ l) + (2/m) + (3/n) 1 2 3/25/2

a, b, c x2 − kx + 2b101 − a101 − c101 = 0(k ∈ R)

x2 − (a + 3)|x| = 4 = 0 a ( − ∞, − 7] ∪ [1, ∞) ( − 3, ∞) ( − ∞, − 7] [1, ∞)

Page 65: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

390

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are the sides of a triangle, then the minimum value of is equal to (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

391

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If then the minimum value of is (a) (b) (c) (d)none of these

Watch Free Video Solution on Doubtnut

392

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If is always (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

393

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If is always (a) (b) (c) (d)none of these

Watch Free Video Solution on Doubtnut

394

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If , then the minimum value of is equal to (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

395

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If and are in H.P., then (a) (b) (c) (d)none of these

Watch Free Video Solution on Doubtnut

a, b, c + +a

b + c − a

b

c + a − b

c

a + b − c3 6 9 12

a, b, c, d ∈ R± 1, (log)da + (log)bd + (log)ac + (log)cb 4 2 1

a, b, c ∈ R+ , then + +bc

b + c

ac

a + c

ab

a + b≤ (a + b + c)

1

2≥ √abc

1

3≤ (a + b + c)

1

3≥ √abc

1

2

a, b, c ∈ R+ then(a + b + c)( + + )1

a

1

b

1

c≥ 12 ≥ 9 ≤ 12

a, b, c ∈ R+ a(b2 + c2) + b(c2 + a2) + c(a2 + b2) abc 2abc 3abc 6abc

a, b, c, d ∈ R+ a, b, c, d a + d > b + c a + b > c + d a + c > b + d

Page 66: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

396

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

If such that , then the maximum value of is equal to

Watch Free Video Solution on Doubtnut

397

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

The minimum value of is

Watch Free Video Solution on Doubtnut

398

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

If then least value of is (a) (b) (c) (d)d. none of these

Watch Free Video Solution on Doubtnut

399

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

Watch Free Video Solution on Doubtnut

400

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are positive numbers is (a) (b) (c) (d) none of these

Watch Free Video Solution on Doubtnut

401

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

For positive real numbers such that which one holds? (a) (b)

(c) (d) none of these

Watch Free Video Solution on Doubtnut

a, b, c, d ∈ R+ a + b + c = 18 a2b3c4 218 × 32 218 × 33 219 × 32 218 × 33

|2z − 1| + |3z − 2|

a > 0, (a3 + a2 + a + 1)2

64a2 16a4 16a3

∫1

(1 − x2)√1 + x2

x, y, z A.P ., then y2 ≥ xz xy + yz ≥ 2xz + ≥ 4

x + y

2y − x

y + z

2y − z

a, bc a + b + c = p, (p − a)(p − b)(p − c) ≤ p38

27(p − a)(p − b)(p − c) ≥ 8abc

+ + ≤ pbc

a

ca

b

ab

c

Page 67: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

402

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If first and terms of an AP, GP. and HP. are equal and their nth terms are a, b, c respectively, then (a) a=b=c (b)a+c=b (c) a>b>c and (d) none of these

Watch Free Video Solution on Doubtnut

403

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

For , the smallest value of the function is

Watch Free Video Solution on Doubtnut

404

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Let has two positive roots , then minimum value if is,

Watch Free Video Solution on Doubtnut

405

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Miscellaneous

If are posirive real umbers and . The maximum value of equals.

Watch Free Video Solution on Doubtnut

406

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are positive and then the maximum value of is (base of the logarithm is 10).

Watch Free Video Solution on Doubtnut

407

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

Given that are positive real such that If the minimum value of is equal then the value of is.

Watch Free Video Solution on Doubtnut

(2n − 1)thac − b2 = 0

x ≥ 0 f(x) = ,4x2 + 8x + 13

6(1 + x)

x2 − 3x + p = 0 aandb ( + )4

a

1

b

x, y, andz x =12 − yz

y + zxyz

a, b, andc 9a + 3b + c = 90, (log a + log b + log c)

x, y, z xyz = 32. x2 + 4xy + 4y2 + 2z2 m, m/16

Page 68: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

408

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If satisfying then the maximum value of is.

Watch Free Video Solution on Doubtnut

409

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

For any . Then the minimum value of is.

Watch Free Video Solution on Doubtnut

410

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

If are positive real numbers, then prove that (2004, 4M)

Watch Free Video Solution on Doubtnut

411

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

The least value of the expression is a. 10 b. 2 c. ­0.01 d. none of these

Watch Free Video Solution on Doubtnut

412

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

The product of positive numbers is unity. Then their sum is a. a positive integer b. divisible b equals to never less than

Watch Free Video Solution on Doubtnut

413

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are different positive real numbers such that are positive, then is a. positive b. negative c. non­positive d. non­negative

Watch Free Video Solution on Doubtnut

x, y ∈ R+ x + y = 3, x2y

x, y, ∈ R+ , xy > 0 + +2x

y3

x3y

3

4y2

9x4

a, b, c, (1 + a)(1 + b)(1 + c)7 > 77a4b4c4

2(log)10x − (log)x(0. 01), f or x > 1,

n n n + 1/n n

a, b, c b + c − a, c + a − b, anda + b − c(b + c − a)(c + a − b)(a + b − c) − abc

Page 69: CHAPTER SEQUENCES AND SERIES || ALGEBRA CENGAGE / G …€¦ · cengage_maths_algebra_sequences and series_progression The sum of some terms of G.P. is 315 whose first term and the

414

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

If are positive real umbers such that ,then satisfies the relation (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

415

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Arithmetic Mean Of Mth Power

If are positive real numbers whose product is a fixed number then the minimum value of is is b.

Watch Free Video Solution on Doubtnut

416

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Weighted Means

If is always greater than or equal to (a) (b) (c) (d)

Watch Free Video Solution on Doubtnut

417

CENGAGE_MATHS_ALGEBRA_SEQUENCES AND SERIES_Inequalities Involving Simple A.M. G.M. H.M.

The minimum value of the sum of real number is

Watch Free Video Solution on Doubtnut

Download Doubtnut to Ask Any Math Question By just a click

Get A Video Solution For Free in Seconds

Doubtnut Has More Than 1 Lakh Video Solutions

Free Video Solutions of NCERT, RD Sharma, RS Aggarwal, Cengage (G.Tewani), Resonance DPP, Allen, Bansal, FIITJEE, Akash,Narayana, VidyaMandir

Download Doubtnut Today

a, b, c, d a + b + c + d = 2 M = (a + b)(c + d) 0 ≤ M ≤ 1 1 ≤ M ≤ 22 ≤ M ≤ 3 3 ≤ M ≤ 4

a1, a2, , an c, a1 + a2 + + an−1.......... . + 2anan−1 + 2an (n + 1)c1 /n 2nc1 /n (n + 1)(2c)1 /n

α ∈ (0, ), then√x2 + x +π

2

tan2 α

√x2 + x2 tanα 1 2 sec2 α

a−5, a−4, 3a−3, 1, a8, anda10witha > 0


Recommended