Date post: | 03-Jun-2018 |
Category: |
Documents |
Upload: | amit-kumar |
View: | 248 times |
Download: | 1 times |
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 1/46
Paper I I
( CALCULUS )
Prof. R. B. Patel Art, Science & Comm. College,
Shahada
Dr. B. R. Ahirrao Jaihind College, Dhule
Prof. S. M. Patil Art, Science & Comm.
College, Muktainagar
Prof. A. S. Patil Art, Science & Comm.
College, Navapur
Prof. G. S. Patil Art, Science & Comm. College, Shahada
Prof. A. D. Borse Jijamata College,
Nandurbar
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 2/46
n
Unit I
Limit, Continuity, Differentiability and Mean Value Theorem
Q.1 Objective Questions Marks – 02
1. lim x2− 4 x − 5
is equal to x→5 x2
+ 2 x − 35
a) 1 b)1 2
2. limcos x
is equal to
c)−1 2
d) none of these
x→1 x −1
a) 0 b) 1 c) -1 d) none of these
3. Evaluate lim x − tan x
a)−1 3
x→0 x3
b)1 3
c) 0 d) 1
4. The value of the limlog(sin 2 x)
is x→0 log (sin x)
a) 2 b) 0 c)1 d) -1
5. lim x is equal to
x→∞ e x
a) 1 b) -1 c) 2 d) 0
6. limlog(sin ax)
x→0 log(sin bx), (a,b > 0) is equal to
a) -1 b) 1 c) 0 d) none of these
7. lim x log x x→0
is equal to
a) 0 b) 1 c) 2 d) -1
8. lim ⎡ 1 − 1 ⎤ is equal to x→0 x sin x
a) 0 b)1 c) -1 d) none of these
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 3/46
⎣ ⎥
⎣ ⎥
9. lim⎡ 1
− 1 ⎤
x→0 ⎢ x e x −1⎢
a) 1 b)
is equal to
−1
2 c)
1 2
d) 0
10. lim x
x
x→0 is equal to
a) 1 b) -1 c) 2 d) none of these
11. lim ( tan x )tan 2 x
is x→π
4
a) e b)1 e
c)−1
e d) – e
12. The function f ( x) = x sin
1
x , for x ≠ 0 and
f (0)=
0 , for x=0
a) Continuous and derivable
b) Not continuous but derivable
c) Continuous but not derivable
d) Neither continuous nor derivable at the point x = 0
13. The function f ( x) = x2 sin
1
x , for x ≠ 0 and
is
f (0) = 0 , for x = 0
a) Continuous and derivable
b) Not continuous but derivable
c) Continuous but not derivable
d) Neither continuous nor derivable
14. For which value of c∈ (a,b) , the Roll‟s theorem is verified for the function
⎡ x 2 +ab ⎤ f ( x) = log ⎢
x(a + b)⎢
defined on [a, b]
a) Arithmetic mean of a & b b) Geometric mean of a & b
c) Harmonic mean of a & b d) None of these .
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 4/46
15. For which value of c∈ (a,b) = (0, 2π ) , the Rolle‟s theorem is applicable for
the function f ( x) = sin x , in [0, 2π ]
a) 0 b)π
c) π
d)π
4 2 3
16. For which value of
c∈ ⎛
0,
π ⎞ , the Rolle‟s theorem is applicable for the⎢ 2 ⎢
function
⎝ ⎟
f ( x) = sin x + cos x in⎡0,π ⎤
2
a) 0 b) π
c) π
d)π
4 3 6
17. For which value of c∈ (1, 5) , the Rolle‟s theorem is verified for the function
f ( x) = x2 − 6 x + 5 in [1, 5]
a) 1 b) 2 c) 3 d) 4
18. for which value of c∈
(-2, 3) . the L.M.V.T. is verified for the function
f ( x) = x2 − 3 x + 2
a) 1 b)1 2
in [−2, 3]
c)−1 2
d) 0
19. L.M.V.T is verified for the function f ( x) = 2 x2 − 7 x +10 in [2, 5]
a)
5 2 b)
1 2 c) 0 d)
7 2
20. For which value of
c∈ ⎛
0,π ⎞
C.M .V.T. is applicable for the function⎢ 2⎢
⎝ ⎟
f(x) = sin x , g(x) = cos x in [0, π/2]
a) 0 b)π
c)π
d)π
3 6 4
21. If the C.M.V.T. is applicable for the function
f(x) = ex , g(x) = e-x , in [a, b] find the value of c∈ (a,b)
a)a +b
2 b) ab c) a + b d) none of these
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 5/46
1
⎝ ⎟
22. If the C.M.V.T. is applicable for the function
f(x) =1/x2 , g(x) = 1/x , in [a, b] find the value of C.
a)a +b
2 b) ab c)
2ab
a + b d) none of these
23. If f ( x)=
log x − log 5 x − 5
, x ≠ 5is continuous at x = 5 then find f(5)
a) 5 b) -5 c)1 5
d)−1 5
24. If f ( x) = 1− sin x
(π − 2 x)2
, x ≠ π
2 is continuous at x =
π
2 then f(π/2) is
a)1 8
25. If
b)2 3
f ( x) = 1− cos x sin x
, x ≠ 0
c) 1 d) -1
is continuous at x = 0 then value of f(0) is
a) 0 b) 1 c) -1 d) none of these
26. I f f ( x) = a
x− a
a
a − x , x ≠ a is continuous at x = a , then find f(a)
a) aa log a b) −aa log a c) log a d) none of these
27. Evaluate lim sin x log x x→0
a) 0 b) 1 c) -1 d) π 2
28. Evaluate lim tan x log x . x→0
a) 0 b) 1 c)-1 d) none of these
29. ⎡ 1 1 ⎤
lim ⎢ − ⎢ x→1 ⎣ log x x −1⎥ is equal to
a)−1 2
b)1 2
c) 2 d)-2
30.
1−cos x
lim⎛ ⎞
x→0⎢ x
⎢
is equal to
a) -1 b) 1 c) 2 d)1 2
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 6/46
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 7/46
x→a⎢ a
x
x
Q.2 Examples Marks – 04
1. Evaluate limtan x − x
x→0 x − sin x
e x −1− x
2. Evaluate lim x→0 log(1 + x) − x
3. Evaluate limlog(tan 2 x)
x→0 log(tan x)
4. Evaluate lim⎛ 1
− cot2 x⎞
x→0⎢ x
2 ⎢ ⎝ ⎟
5. Evaluate lim⎛
2− ⎝
tan(π x ) x ⎞ 2a
⎢ ⎟
6. Evaluate lim(cot x) x x→0
, x > 0
7. Evaluate lim(cot x) x→0
1 log x
1
8. Evaluate lim⎡π
− tan −1 x⎤
x ⎢ 2 ⎢ →∞ ⎣ ⎥
9. Examine for continuity, the function
x2
f ( x) = − a,
a
for 0 < x < a
= 0 ,
a3
forx = 0
= a − x2
, forx > a
10. Using ∈ −δ definition , prove that
f ( x) = x2 cos1
, x
= 0 ,
if x ≠ 0
if x = 0
is continuous at x = 0
11. Examine the continuity of the function 1
f ( x) =e −1
, if x ≠ 0 at the point x = 0.1
e x +1
= 0 , if x = 0
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 8/46
12. Examine the continuity of the function
f ( x) = x2
− 9 ,
x − 3 for 0 ≤ x < 3
= 6 ,
= 8− 18
, x2
for x = 3
for x > 3
at the point x = 3.
13. Examine the continuity of the function
x2
f ( x) = − 4, 4
f or 0 < x < 4
= 2 ,
= 4− 64
, x2
for x = 4
for x > 4
at the point x = 4..
14. If the function
f ( x) =sin 4 x
+ a, 5 x
= x + 4 − b ,
= 1 ,
for x > 0
for x < 0
for x = 0
is continuous at x = 0 , then find the values of a & b.
15. If f(x) is continuous on [−π , π ]
f ( x) = −2 sin x,
= α sin x + β ,
for
for
-π ≤ x ≤ −π
2 -π
< x <π
2 2
Find
= cos x,
α & β .
for π ≤ x ≤ π
2
16. Define differentiability of a function at a point and show that f ( x) = x is
continuous, but not derivable at the point x = 0.
17. Discuss the applicability of Rolle‟s Theorem for the function f ( x) = ( x − a)m ( x − b)n
defind in [a, b] where m, n are positive integers.
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 9/46
3
in ,
4 6⎝ ⎟
18. Discuss the applicability o Rolle‟s Theorem for the function
f ( x) = e x (sin x − cos x) ⎡π 5π ⎤ ⎢⎣ 4 4 ⎢⎥
.
19. Verify Langrange‟s Mean Value theorem for the function
f ( x) = ( x −1)( x − 2)( x − 3) defined in the interval [0, 4] .
20. Find θ
that appears in the conclusion of Langrange‟s Mean Value theorem
for the function f ( x) = x3, a = 1, h =
1.
3
21. Show that b − a
< tan−1 b − tan−1 a <b − a
, if 0 < a < b .1+ b2
And hence deduce that
1+ a2
π +
3< tan−1 ⎛ 4 ⎞
<π
+1
4 25⎢ ⎢
22. For 0 < a < b , Prove that 1− a < log b < b −1 b a a
and hence show that
1< log
6<
1
6 5 5
23. If < a < b <1 , then prove that b − a
< sin −1 b − sin −1 a < b − a
1 − a2
Hence show that π −
1< sin
−1 1< π −
1
1 − b2
6 2 3 4 6 15
24. Show that x
< tan−1 x < x, 1+ x2
x > 0
25. For x > 0 , prove that x2 x2
x − < log(1 + x) < x −2 2(1 + x)
26. Separate the interval in which
decreasing.
f ( x) = x3+ 8 x2
+ 5 x − 2 is increasing or
27. Show that x
< log(1+ x) < x, 1+ x
∀ x > 0
1 tan
−1 x28. Show that <
1+ x2
< 1, x
∀ x > 0
29. With the help of Langrange‟s formula Prove that
α − β α − β π< tanα − tan β < ,
cos2 β cos2 α where0 ≤ β ≤ α ≤
2
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 10/46
( )
,
30. Verify Cauchy‟s Mean Value theorem for the function
f (x) = sinx, g (x) = cosx in 0 ≤ x ≤ π
2
31. Show thatsinα − sin β
cos β − cosα = cot θ , wher e 0 < α < θ < β <
π
2
32. If f ( x) =
1
x2
and g( x) =1
x
in Cauchy‟s Mean Value Theorem, Show that
C is the harmonic mean between a & b.
33. Discuss applicability of Cauchy‟s Mean Value Theorem for the function
f (x) = sinx and g (x) = cosx in [a, b] .
34. Verify Cauchy‟s Mean value theor em f ( x) = x , g( x) = 1
x in[a,b]
35. Find c∈ (0, 9) such that
f (9) − f (0)=
f '(C ) wher e f ( x) = x3 and g( x) = 2− x g(9) − g(0) g '(c)
36. Discuss the applicability o Rolle‟s Theorem for the function
⎡ x2+12 ⎤
f ( x) = log ⎢ ⎢ in 3,4 .
⎣ x ⎥
37. Verify Langrange‟s Mean Value theorem for the function
f ( x) = x( x −1)( x − 2)
in⎡0,
1 ⎤⎢ 2 ⎢ ⎣ ⎥
38. Discuss the applicability o Rolle‟s Theorem for the function
f ( x) = e x cos x in ⎡ -π π ⎤ ⎢⎣ 2 2 ⎢⎥
.
39. Verify Langrange‟s Mean Value theorem for the function
f ( x) = 2 x2 −10 x + 29 in [2, 7] .
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 11/46
Q.3 Theory Questions Marks – 04 / 06
1. If a function f is continuous on a closed and bound interval [ a, b] ,then show
that f is bounded on [a, b].
2. Show that every continuous function on closed and bounded interval attains its
bounds.3. Let f : [a, b] → R be a continuous on [a ,b] and if f (a) < k < f (b), then
show that there exists a point c∈ (a,b) such that f (x) = k.
4. If f (x) is continuous in [a, b] and
every value between f (a) and f (b).
f (a) ≠ f (b) , then show that f assume
5. If a function is differentiable at a point then show that it is continuous at that
point. Is converse true? Justify your answer.
6. State and Prove Rolle‟s theorem OR
If a function f(x) defined on [a,b] is
i)continuous on [a,b] ii) Differentiable in (a, b) iii) f (a ) = f( b)
then show that there exists at least one real number c∈ (a,b) such that f‟(c)=0.
7. State and Prove Langrange‟s Mean Value Theorem. OR
If a function f(x) defined on [a,b] is i) continuous on [a,b]
ii) differentiable in (a, b) then show that there exixt at least one real num ber
f '(c) = f (b) − f (a)
b − a
c∈ (a,b) such that
8. State and Prove Cauchy‟s Mean Value Theorem. OR
If f(x) and g(x) are two function defined on [a,b] such that
i) f(x) and g(x) are continuous on [ a, b]
ii) f(x) and g(x) are differentiable in (a,b) iii) g '( x) ≠ 0, ∀ x∈ (a,b)
then show that there exist at least one real number c∈ (a,b) such that
f '(c)=
f (b) − f (a)
g '(c) g(b) − g(a)
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 12/46
9. State Rolle‟s Theorem and write its geometrical interpretation.
10. State Langrange‟s Mean Value Theorem and write its geometrical
interpretation.
11. If f(x) is continuous in [a,b] with M and m as its bounds then show that f(x)
assumes every value between M and m.
12. Using Langrange‟s Mean Value Theorem show that
cos aθ − cosbθ
θ ≤ b − a, ifθ ≠ 0
13. If f(x) be a function uch that f '( x) = 0,∀ x∈ (a,b) then show that
f(x) is a constant in this interval.
14. If f(x) is continuous in the interval [a,b] and f '( x) > 0,∀ x∈ (a,b) then show
that f(x) is monotonic increasing function of x in the interval [a,b].
15. If a function f(x) is such that i) it is continuous in [a, a+h]
ii) it is derivable in (a, a+h)
iii) f(a) = f(a+h)
then show that there exist at least one real number θ such that f '(a + θ h) = 0,
where 0< θ
<1.
16. If the function f(x) is such that i) it is continuous in [a, a+h]
ii) it is derivable in (a, a+h)
then show that there exists at least one real number θ such that
f (a + h) = f (a) + hf '(a + θ h), where0 < θ
< 1
17. If f(x) is continuous in the interval [a,b] and f '( x) < 0,∀ x∈ (a,b) then show
that F(x) is monotonic decreasing function of x in the interval [a, b].
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 13/46
Unit II
Successive Diff. And Taylor’s Theorem,
Asymptotes, Curvature and Tracing of Curves
Q-1.Question (2-marks each)
1. State Leibnitz theorem for the nth derivative of product of two functions.
2. Write nth derivative of eax .
3. Write nth derivative of sin(ax + b).
4. Write nth
derivative of cos(ax + b).
5. State Taylor ‟s theorem with Langr ange‟s form of reminder after nth term.
6. State Maclaurin‟s infinite series for the expansion of f(x) as power series in
[0,x].
7. Define Asymptote of the curve.
8. Define intrinsic equation of a curve.
9. Define point of inflexion.
10. Define multiple point of the curve.
11. Define Double point of the curve.
12. Define Conjugate point of the curve.
13. Define Curvature point of the curve at the point.
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 14/46
n
n+
n
n
n
n
n
Q-2 Examples ( 4- marks each)
1. If y = x2 + 4 x + 1, find y .
x3 + 2 x2 − x − 2n
2. If y = eax cos2 x sin x, find yn .
3. If y = x2 sin(3 x + 7), find y8.
4. If
y = (sin −1 x)2 Provethat
(1 − x2 ) y n+ 2
− (2n +1) y n+1
− n2 y = 0
If y = cos(m sin −1 x) Prove that 5.
(1 − x2 ) y n+ 2
− (2n +1) xy n+1
+ (m2 − n2 ) y = 0
If y = tan(log y) Prove that 6.
(1 + x2 ) y n+1
+ (2nx −1) y n
+ n(n − 1) yn−1
= 0
7. If
1
y m +y −1
m =2 x Prove t hat
( x2−1) y
n+ 2 + (2n + 1) xy n+1+ (n2 − m2 ) y = 0
If cos−1
( y ) = log ( x )n
Prove that 8. b n
x2 y n+ 2
+ (2n +1) xy n+1
+ 2n2 y = 0
9. Find yn
if y = x2
( x + 2)(2 x +3)
10. Find y if y = cos4 x
11.
If y = a cos(log x) + bsin(log x) Prove t hat
x2 y n+ 2
+ (2n + 1) xy n+1
+ (n2 + 1) y = 0
12. If y = tan −1 x Prove that
(1 + x2 ) y + 2(n +1) xy n+1
+ n(n +1) yn
= 0
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 15/46
n
(
−1
n+
n
3 4 5
n )
n
) n
n
13. Find y if y = e x log x
14. Find yn
if y = cos x cos 2 x cos 3 x
15.
If y = sin2 x cos2 x
n
Prove that
y = −4 .cos 4 x + nπ 8 2
16. If y=(x 2 -1)n
Prove that
( x2 −1) y n+ 2
+ 2 xyn+1 − n(n +1) y
n= 0
17. If y = emcos x
Prove that
( x2− 1) y
n+ 2 − (2n + 1) xy n+1− (n2 + m2 ) y = 0
18. If y = ( x +
m
x2 − a2 Prove that
( x2 − a2 ) y + (2n +1) xy n+1 + (n2 − m2 ) y = 0
19. If y = sin(m sin −1 x) Prove that
(1 − x2 ) y n+ 2 − (2n +1) xy n+1
− (n2 − m2 ) y = 0
20. If y = cos(log x) Prove that
x2 y n+ 2
+ (2n + 1) xy n+1
+ (n2 + 1) y = 0
21. Use Taylor‟s theorem to express the polynomial
of ( x-2 ) .
22. Expand sinx in ascending powers of ( x − π 2 )
2 x3 + 7 x2 + x − 6 in powers
23. Assuming the validity of expansion , prove that
e x cos x = 1 + x − x
− x
− x
+ −−− − 3 6 30
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 16/46
3 5 7
24. Assuming the validity of expansion , prove that
x2 2 x4 16 x5
sec x = + + + −−−− 2! 4! 6!
25. Expand log(sinx) in ascending powers of ( x- 3).
26. Expand tanx in ascending powers of ( x − π 4 ) 27. Prove that tan−1 x = x −
1 x3 +
1 x5 -------- and hence find the value of π
3 5
28. Prove that sin−1 x = x + 12. x
+ 12.32. x
+ 12.32.52. x
= −− −− 3! 5! 7!
2 ( tan x − sin x) − x3
29. Use Taylor‟s theorem ,Evaluate lim x→0 x5
30. Expand e x in ascending powers of ( x- 1).
31. Expand 2 + x2− 3 x
5 + 7 x6 in power of ( x-1 ).
32. Obtain by Maclurin‟s theorem the first five term in the expansion of
log(1 + sin x) .
33. Obtain by Maclurin‟s theorem the expansion of log(1 + sin2 x) upto x4.
34. Assuming the validity of expansion , prove that
esin x = 1+ x + 1
x2−
1 x4 + − − − − −
2 8
35. Find the asymptotes of the curve y = x x2 − 4
36. Find the asymptotes of the curve y = x − 2 + x2
x2 + 9
37. Find the asymptotes of the curve y = 3 x2 − x3
38. Find the asymptotes of the curve x = t , y = t + 2 tan−1 t
39. Find the asymptotes of the curve x2
y =
x2 − 4
40. Find the asymptotes of the curve x3
y = x
2+ x − 2
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 17/46
2
41. Find the differential arc and also the cosine and sine of the angle made by the
tangent with positive direction of X-axis . for the curve y2 = 4ax.
42. Find the differential of the arc of the curve r = a cos2 (θ ) .Also find the sine
ratio of the angle between the radius vector and the tangent line.
43. Find the point on the parabola y2 = 8 x at which curvature is 0.128.
44. Find the curvature of r2 = 2a2 cos 2θ , at θ = π .
45. Find the curvature and radius of curvature at a point “t” on the curve,
x = a(cos t + t sin t), y = a(sin t − t cos t) .
46. Find the curvature of the curve, y = x − x2 at P (1, 0) .
47. Find the curvature of the curve, y = x4 − 4 x3 − 18 x2 at origin .
48. Find the curvature of the curve, y3 = x at P (1,1) .
49. Examine for concavity and point of inflection of Guassian Curve y = ௫మ
50. Trace the curve y = ( x −1)2 ( x + 2)
51. Trace the curve y = x(1− x)3
52. Find the asymptotes parallel to co-ordinate axes for the curve
y2 ( x2 − a2 ) = x
53. Find the radius of curve of y = c tanψ .
54. Show that the curvature of the point (3a 2 , 3a
2 ) on the folium
x3 + y3 = 3axy is −8 2
3a
13
55. Find the point on the parabola y2
= 8 x at which radius of curvature is 7 16 .
56. Examine the nature of the origin of x3 + y3 − 3axy = 0 .
57. Trace the curve x
3
+ y
3
= 3axy .
58. Trace the curve xy2 = a2 (a − x) .
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 18/46
∫
Unit III
Integration of Irrational Algebraic and Transcendental Functions,
Applications of Integration
Q-1 Marks - 02
1. The proper substitution for the integral of the type
dx is − − − − − ∫
( px + q)
2. Evaluate
3. Evaluate
ax + b
dx
∫2 x x − 4
dx
∫ (1− 3 x) x + 2
4. Evaluate
5. Evaluate
dx ∫
(2 − x) 1− x
dx
∫ x 3 x + 2
6. Evaluate
7. Evaluate
dx ∫
(1− 2 x) 2 − x
dx
∫ (2 x − 3) x
8. Evaluate dx
∫ (4 x + 1) x − 2
9. Evaluatecos x.dx
(2 sin x −1) 2− sin x
e xdx10. Evaluate ∫ x
(2e + 3) e x− 4
π
2
11. Reduction formula for ∫ sinn xdx i s − − −−
0
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 19/46
π 2
12. Evaluate ∫ sin9 xdx
0
= -------------
π
2
13. Evaluate ∫ sin6 xdx
0
π
2
14. Evaluate ∫ sin7 xdx
0
π
2
15. Reduction formula fpr ∫ cosn xdx
0
= −−−−
π 2
16. Evaluate ∫ cos8 xdx
0
π 2
17. Evaluate ∫ cos9 xdx
0
π
4
18. Evaluate ∫ sin4
2 xdx 0
π
x 19. Evaluate ∫ sin5 dx
02
a
x
5
20. Evaluate ∫ 2 2dx
0 a − x
21. Evaluate ∞
dx ∫ 2 2 4
0(a + x )
∞
dx 22. Evaluate ∫ 5
0 (1+ x2 ) 2
23. Evaluate ∫ sin3 x. cos4 xdx
24. Evaluate ∫ sin6 x. cos5 xdx
25. Evaluate ∫ sin4 x. cos6 xdx
26. Evaluate ∫ sin5 x. cos7 xdx
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 20/46
π 2
27. Evaluate ∫ sin5 x. cos
4 xdx
0
π
2
28. Evaluate ∫ sin8 x. cos
5 xdx
0
π
2
29. Evaluate ∫ sin4 x. cos
8 xdx
0
π
2
30. Evaluate ∫ sin5 x. cos
9 xdx
0
31. The proper substitution for the integral of the type
dx∫ 2
( px + qx + r) ax2+ bx + c
is ----------
32. The length of the arc of the curve y = f(x) between the points x = a , x = b is
given by S = ---------------- with usual notation.
33. The length s of the arc of the curve x = f (t) ,y = ψ (t) between the points
where t = a , t = b is given by S = ------------ with usual notations.
34. The equation of the Catenary is ----------
35. The equation of the Astriod is ----------
36. The volume of the solid generated by revolving about X-axis , the area
bounded by the curve y = f(x) , the X- axis and the ordinate x = a , x = b is
given by V = ------------- with usual notation .
37. The volume of the solid generated by Revolving about X-axis ,the area
bounded by the curve x = g (y) , the Y-axis and the abscissas y = c , y = d is
given by V= ---------------with usual notation .
38. The volume of the solid generated by revolving about X-axis , the area
bounded by the parametric curve X = φ (t) ,Y = ψ
(t ) and the ordinate t = a
, t = b is given by V = ------------- with usual notation .
39. The volume of the solid generated by revolving about Y-axis , the area
bounded by the parametric curve Y= φ (t) ,Y = ψ
(t ) and the abscissas t =
a , t = b is given by V = ------------- with usual notation.
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 21/46
40. The volume of the solid generated by revolving about X-axis , the area
bounded by the curve Y1 = φ (x ) ,Y2 = ψ
(x ) and the ordinates x = a , x =
b is given by V = ------------- with usual notation.
41. The Volume of the sphere of radius a is --------------
42. The volume of the ellipsoid formed by revolving the ellipse x 2 y 2
+ = 1
about Y-axis is --------
a2 b2
43. The area of the curved surface of the solid generated by revolving about X-
axis , the area bounded by the continuous curve y = f( x) , the X-axis and the
ordinates x = a , x = b is S=-------------
44. The area of the curved surface of the solid generated by by revolving about
Y-axis , the area bounded by the continuous curve g = f( y) , the Y-axis and
the abscissae y = c , y = d is S=-------------
45. The area of the curved surface of the solid generated by by revolving about
X-axis , the area bounded by the curve x = φ (t), y = ψ ( t) , the X-axis and
the ordinates t = a , t = b is S =------------- whereds
= − − − − − dt
46. The surface area of the sphere of radius a is -----------
47. Write down the parametric equation of the cycloid.
π 1 xn 2
48. ∫ 2
0 1− x dx = ∫
− − − −
0
∞1
π 2
49. ∫ (1+ x2 )n dx = ∫ − − − −
0 0
50. Define i) A rectification
ii) A cap of the sphere.
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 22/46
Q-2 (4-marks each)
Integral of the form dx
1. Evaluate
∫ ( px2
+ qx + r)
dx
ax + b
∫ ( x2
+1) x
2. Evaluate dx
∫ ( x2 − 2 x + 2) x −1
3. Evaluate
4. Evaluate
dx ∫
(2 x2 − 2 x +1) 2 x −1
dx
∫ ( x2
+ 5 x + 8) x + 3
5. Evaluate dx
∫ ( x2 − 2 x + 2) x −1
6. Evaluate dx
∫ ( x2 − 4 x + 5) x − 2
Integral of the form dx
7. Evaluate
8. Evaluate
∫ ( px + q)
dx ∫ 2 x x + x +1
dx
ax2+ bx + c
∫ (1− x) x2
+1
9. Evaluate
10. Evaluate
dx
∫2 x x + x + 2
dx
∫ (1− x) x2
+ 2
11. Evaluate dx
∫ (1− 2 x) x2
+ x
12. Evaluate
dx
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 23/46
∫ ( x +1) x2
+1
13. Evaluate dx
, ( x ≥ 1)
∫ ( x−
1) x2
+ x +1
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 24/46
4
14. Evaluate dx
∫ x 1 − 2 x − x2
15. Evaluate dx
∫ ( x +1) x2
+ x +1
Integral of the form dx
16. Evaluate
17. Evaluate
∫ 2 ( px + qx + r)
dx ∫ 2 2
(1+ x ) 1− x
dx
ax2+ bx + c
∫2 ( x + 4) x2
+1
18. Evaluate dx
∫ 2 ( x −1) x2
+1
19. Evaluate dx
∫ 2 ( x + 2) x2
+1
Reduction formula type examples-
13
dx 20. Evaluate ∫ 2 2
0 (1+ x ) 1− x
1
9 7
21. Evaluate ∫ x 2 (1 − x) 2 dx
0
a
22. Evaluate ∫ x4
0
a2− x2dx
1
23. Evaluate ∫ x
dx 2
0 1 − x
24. Evaluate ∞ dx
∫ 5
0 (1+ x2 ) 2
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 25/46
dx
dx
∫
∫
8
3
7
2
2
7
2
7
3
25
9
1
25. Evaluate ∫ x
dx 2
0 1 − x 1
26. Evaluate ∫ x6
0
1 − x2dx
1 2
27. Evaluate ∫ x7
0
1+ x dx 1− x2
4
28. Evaluate ∫ x 0
4 x − x2dx
∞
29. Evaluate ∫ x
dx 2
0 (1+ x )∞
30. Evaluate ∫ x
dx 2
0 (1+ x )∞
31. Evaluate ∫ x
dx 2
0 (1+ x )∞
32. Evaluate ∫ x
dx 2
0 (1+ x )
∞ x4
33. Evaluate ∫ 2 4
0(1 + x )
∞ x3
34. Evaluate ∫ 2 3
0(1 + x )
35. Evaluate ∞
⎛ = x ⎞6
dx⎢ 2 ⎢ 0 ⎝ 1+ x ⎟
36. Evaluate ∞
⎛ = x ⎞5
dx⎢ 2 ⎢ 0 ⎝ 1+ x ⎟
37. Show that
4
∫ x2
0
4 x − x2 dx = 10π
38. show that
1
∫ x2
0
x − x2 dx =5π
128
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 26/46
∫
6
39. show that ∫ x 0
6 x − x2dx =
27π
2
40. show that
2
∫ x3
0
2 x − x2 dx =7π
8
41. Let In = ୱ୧୬ ௫ୱ୧୬ ௫
, 1 show that
In =ଶ ୱ୧୬ሺଵሻ ௫
ଵ + In-1 Where n is a positive integer.
sin 6 x ⎡ sin 5 x sin 3 x ⎤ Show that∫ dx = 2 + + sin x
42. sin x 5 3
πsin 6 x
Hence Show that∫ dx = 0
0sin x
sin 7 x ⎡ sin 6 x sin 4 x sin 2 x x ⎤ Show that∫ dx = 2 + + +
43. sin x
π
6 4 2 2
sin 7 x Hence Show that∫ dx = π
0sin x
44.
Let I 22
sin 22 x
= ∫ sin xdx,
Show that I
= 2⎛ sin 21 x
+sin 19 x ⎞
+ I 22 ⎢
21 19⎢ 18
⎝ ⎟
45. sin 5 x
Show that dx = sin 2 x(3− 2 sin2 x) + x sin x
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 27/46
2
Q3. (6-marks each)
Reduction formulae
1. Evaluate ∫ sinm x. cosn xdx , where m, n are positive integers.
π 2
2. Evaluate ∫ sinn xdx , where n is positive integers.
0
π 2
3. Evaluate ∫ cosn xdx , where n is positive integers.
0
π 2
4. Evaluate ∫ (sin x)m .(cos x)n dx , where m and n are positive integers. 0
∞
5. Evaluate ∫ 1
n+ 1 dx , where n is a positive integers.
0 (1+ x2 ) 2
Application of Integration.
Rectification –
6. Show that the length of an arc of the parabola y2= 4a x cutoff by the y = 2x
is ⎡ 2 + log(1+
2 )⎤ .⎣ ⎥
7. Show that the length of an arc of the parabola x2= y form the vertex to any
extremity of the latus rectum is1
+1log(1+ 2 ).
2 2 4
8. Show that the length of the arc of the curve y = x2 cutoff by the line
x – y = 0 is1 ⎡2 5 + log(2 +
5 )⎤ .
4⎣ ⎥
9. Find the length of an arc of the catenary
vertex (0 , c) to any point (x, y ).
y =c (e
xc + e
− xc ) measured from the
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 28/46
10. Find the length of an arc of the curve y = sin−1e
x between the points where
y =π
and y =π
.6 2
11. Using theory of integration , obtains the circumference of the circle
x2+ y2
= 25.
12. Find the length of an arc of the cycloid
x = a(θ − sinθ ), y = eθ ⎛ cos
θ − 2 sin
θ ⎞ between the cupsθ
= 0 and
θ = 2π .⎢
2 2⎢
⎝ ⎟
13. Find the length of an arc of the curve x = eθ ⎛
sinθ
+ 2 cosθ ⎞
,
⎢ 2 2
⎢
y = eθ ⎛ cosθ − 2 sin
θ ⎞ between the cupsθ = 0 and
⎝ ⎟
θ
= π
.⎢ 2 2
⎢ ⎝ ⎟
14. Find the length of an arc of the curve x = a(2cosθ
− cos 2θ ),
y = a(2 sinθ − six2θ ),
89.
measured from the points, where θ = 0 and θ = π
is
15. Find the length of an arc of the curve x = a(cosθ
+ θ
sinθ ),
y = a(sinθ
− θ
cosθ ), from the points, wher e θ = 0 and θ = 2π is 2π 2 a .
Volumes of Solids of Revolution
16. Using theory of integration , show that the volume of sphere of radius „a „ is
4π a3cubic units .
3
x 2 y 2
17. Show that the volume of solid genered by revolving the ellipse + = 1 ,
about X-axis is4π ab2cubic units .
3
a2 b2
18. Find the Volume of the solid formed by revolving the arch of the cycloid
x = a(θ − sinθ ) , y = a(1− cosθ ) about its base.
19. The area enclosed by the hyperbola xy = 12 and the line x + y =7 is revolved
about X-axis , Show that the volume of the solid generated is
π cubic units
3
20. Compute the volume of the solid generated by revolving about Y-axis , the
region enclosed by the parabolas y = x2 and 8 x = y 2 .
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 29/46
3
Areas of surface s of revolution-
21. The are of the parabola y2= x between the origin and the point (1,1) is
revolved about X-axis , Find the area of the surface of revolution of the solidformed .
22. Find the surface area of the solid generated by the revolution about the X-axis
of the loop of the curve x = t 2 , y = t − t
. 3
23. The arc of the parabola y2= 4 x between its vertex and an extremity of its latus
rectum revolves about its axis. Find the surface area traced out.
24. If the segment of a straight line y = 2x between x = 0 to x = 1 is r evolved
about Y-axis .show that surface area of the solid so formed is
4 5π square units .
25. Find the area of the surface generated when the segment of the straight line
y = x between x = 0 to x = 1 is revolved about Y-axis.
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 30/46
Unit – IV
Differential Equation of First Order & First Degree
Q-1 04 or 06 Marks
1. Explain the method of solving homogeneous diff. Equation of the type
Mdx + Ndy = 0, where M = M(x, y), N = N(x, y)
2. Explain the method of solving non-homogeneous diff. Equation
=
భ ௫భ௬భ , where a , b , c , a , b ,
c are real numbers.
మ௫మ௬మ
1 1 1 2 2 2
3. Explain the method of solving exact diff. Equation Mdx + Ndy = 0,
where M = M(x, y), N = N(x, y)
4. If the diff. Eq. Mdx + Ndy = 0 is homogeneous thenଵ
௫௬
= 0 is an
integrating factor, where Mx + Ny ≠ 0 and M = M(x, y), N = N(x, y)
5. If the diff. Eq. Mdx + Ndy = 0 is of type f 1(x, y)ydx + f 2(x, y)xdy = 0 then
ଵ
௫௬= 0 is an integrating factor, where Mx - Ny ≠ 0.
ಢM
ಢN
6. IFಢ౯ ಢ౮
N
is a function of x alone then
ሺ௫ሻ ௫ is an integrating factor of
equation Mdx + Ndy = 0 where M = M(x, y), N = N(x, y)ಢN
ಢM
7. IFಢ౮ ಢ౯
M is a function of y alone then
ሺ௬ሻ ௬ is an integrating factor of
equation Mdx + Ndy = 0 where M = M(x, y), N = N(x, y)
8. Solve the linear diff. Equation
only.
9. Solve the linear diff. Equation
only.
+ Py = Q , where P & Q are functions of x
+ Px = Q , where P & Q are functions of y
10. Explain the method of solving the diff. Equation F(x, y, p ) = 0, which is
solvable for p, where p = .
11. Explain the method of solving the diff. Equation F(x, y, p ) = 0, which is
solvable for y, where p = .
12. Explain the method of solving the diff. Equation F(x, y, p ) = 0, which is
solvable for x, where p = .
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 31/46
Q-2 04 Marks
Solve the following differentials equations
1. sec2x tany dx + sec2y tanx dy = 0
2. y sec2x dx + (y+7) tanx dy = 0
3. =
ሺଶ୪୭ሻ
ୱ୧୬
+ycosy
4. (y-x
) = a(y
2+ )
5. (x2-yx
2)dy + (y
2+xy
2)dx = 0
Solve the homogeneous diff. Eq.
6. (x3+y3)dx – 3xy2dy = 0
7. x2dy + (y2-xy)dx = 0
8. (x2+xy-y2) dy + (2xy -3y2)dx = 0
9. xdy – ydx = ඥ ଶ ଶ dx
10. x2
= y(x+y)/2
11. (x2-y2) dx + 2xy dy = 0
12.
13.
ሺమ–
మሻ
=
ሺమ– మሻ
= ଶ
14. (x2+y
2)
= xy
15. ( x + y cotx/y ) dy – y dx = 0
Solve the Non-homogeneous diff. Eq.
16. ሺଶ
– ହ ଷሻ =
ሺሻ
17. (2x – y + 1) dx + (2y – x - 1)dy = 0
18.
19.
20.
ሺ – ସ ଷሻ =
ሺଵሻ
ሺ ଵሻ =
ሺଵሻ
ሺ ଶ ଵሻ =
ሺሻ
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 32/46
21. ሺ ଶ ሻ
= ሺଶଷସሻ
22. ሺ –
ଵሻ =
ሺହሻ
23. ሺଶ – ଵሻ
= ሺଶଷሻ
24. ሺସ
– ଷሻ =
ሺሻ
Solve the exact diff. Eq.
25. (2x2 + 3y)dx + (3x + y - 1) dy = 0
26.
ୡ୭ୱୱ୧୬ + = 0
ୱ୧୬ ୡ୭ୱ
27. (x2 + y2 - a2) x dx + (x2 – y2 - b2) y dy = 0
28. (1 + ) dx + [ (1 – x/y] dy = 0
29. (secx tanx tany - ex) dx + secx sec2x dy = 0
30. (x2 – 4xy – 2y2) dx + (y2
– 4xy + 2x2) dy = 0
31. (ey
+ 1) cosx dx + ey
sinx dy = 0
32. (sinx cosy + e2x) dx + (cosx siny + tany) dy = 0
33. [x ඥ ଶ ଶ - y] dx + [yඥ
ଶ ଶ - x] dy = 0
34. [cosx tany + cos(x + y)] dx + [sinx sec2y + cos(x + y)] dy = 0
Solve the Non-exact diff. Eq.
35. (x2y – 2xy2) dx – (x3 – 3x2y) dy = 0
36. (x2 – 5xy + 7y2) dx + (5x2 – 7xy) dy = 0
37. (x2y2 + 4xy + 2) x dx – (x2y2 + 5xy + 2 ) ydy = 0
38. (3xy2 – y
3) dx – (2x
2y - xy
2) dy = 0
39. (1 + xy) ydx + (1 - xy) xdy = 0
40. (xy sinxy + cosxy) ydx + (xy sinxy – cosxy) xdy = 0
41. y(xy + 1) dx + x(1 + xy + x2y
2) dy = 0
42. (xy + 2x2y
2) ydx + (xy - x
2y
2) xdy = 0
43. (1/x+y) dx + (1/y-x) dy = 0
44. (x4y
4+ x
2y
2+ xy) ydx + (x
4y
4- x
2y
2+ xy) xdy = 0
45. (x2 + y2) dx – 2xy dy = 0
46. (x2y2 + 2xy + 1) ydx + (x2y2 - xy + 1) xdy = 0
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 33/46
47. (1 + xy) ydx + (1 - xy) xdy = 0
48. (xy3 + y) dx + 2(x2y2 + x + y4) dy = 0
49. (y4
+ 2y) dx + (xy3
+ 2y4 – 4x) dy = 0
50. (x - y2) dx + 2xy dy = 0
51. (3x2y4 + 2xy) dx + (2x2y3 - x2) dy = 0
52. (x2y + y3) dx + (2/3 x3 + 4xy2) dy = 0
53. (x4e
x – 2mxy
2) dx + 2mx
2y dy = 0
54. (x2
+ y2
+ x) dx + xy dy = 0
55. (x2 + y2 + 2x) dx + 2y dy = 0
56. (x - y2) dx + 2xy dy = 0
57. (x3
+ xy4) dx + 2y
3dy = 0
58. (2y2 + 3xy – 2y + 6x) dx + x(x + 2y - 1) dy = 0
59. 2y (x + y + 2) dx + (y2 – x2 – 4x - 1) dy = 0
60. (7x4y + y + 2) dx + (x4 + xy) x dy = 0
Solve the Linear diff. Eq.
61.
62.
– 2y = e
2x
+ x2y = x
5
63. sinx
+ 3y = cotx
64. + 2xy + xy4 = 0
65. 3y2 + 2xy3 = 4x ௫
మ
66. (x2y3 - xy) dy = dx
67. xy -
= y3
௫మ
68.
69.
= x(x2 – 2y)
= (2x + 3y - 7)2
70. cosx
+ 2y sinx = sinx cosx
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 34/46
Solve the following diff. Eq. for x, y, p
71. p2 – 5p + 6 = 0
72. p – 1/p = x/y – y/x
73. p(p + y) = x(x+ y)
74. p(p - y) = x(x+ y)
75. p2 – 7p + 12 = 0
76. 2y = ax/p + px
77. 4y = x2 + p2
78. 3x – y + logp = 0
79. y = 2px + x2 p4
80. y – 2px = f(xp2)
81. y = 2px + p2y
82. p3 – 2xyp + 4y2 = 0
83. y = 3px + 6y2 p2
84. y = 2px + y2 p3
85. xyp2 + (x2 + xy + y2)p + x(x + y) = 0
86. 3x – y + log p = 0
87. y = (1 + p)x + p2
88. y2 logy = xyp + p2
89. xp3 = m + np
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 35/46
Que. 3 02 Marks
Write the definition of following
1. Homogeneous differential equation
2. Non- homogeneous differential equation
3. Exact differential equation
4. Linear differential equation
5. Bernaoll‟s differential equation
6. Claraut‟s differential equation
Find the integrating factor of the following differential equation
7. (1 + y2) dx + (x - షభ௬) dy = 0
8. +
9. -
ସ௫
௫మ ଵ
ଵ
௫
ଵ y =
ሺ௫మ ଵሻ య
tany = (1 + x) ex secy
10. (x cosx)
+ (x sinx + cosx) y = 1
11. = x3y3 - xy
12. (xy3
+ y) dx + 2(x2y
2+ x + y
4)dy = 0
13. (x2 + y2 + 2x) dx + 2ydy = 0
14. (y4 + 2y) dx + (xy3 + 2y4 – 4x) dy = 0
Multiplying by appropriate integrating factor, make following diff. Eq. Exact.
15. (x2y2 + 2) ydx + (2 – 2x2y2) dy = 0
16. (x2y2 + xy + 1) ydx + (x2y2 – xy + 1) dy = 0
17. (3xy2 – y
3) dx - (2x
2y - xy
2) dy = 0
18. (x2
+ y2
) dx – 2xy dy = 019. (7x4y + 2xy2 – x3) dx + (x4 + xy) xdy = 0
20. (x2
+ y2
+ x) dx + xy dy = 0
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 36/46
A)
C)
Not exact D. E.
Linear D. E.
B)
D)
Clairaut‟s D. E.
Homogeneous D. E.
The diff. Eq. y = px +ඥ4 ଶ is ---
A)
C)
Non-homogeneous D. E.
Bernaoll‟s D. E.
B)
D)
Clairaut‟s D. E.
Homogeneous D. E.
Write the appropriate answer of the following, where P & Q are functions of x only.
21. The diff. Eq.
+ Py dy = Q is ---
A) Linear D. E. B) Bernaoll‟s D. E.
C) Exact D. E. D) Not exact D. E.
22. The diff. Eq. (x2 + y2)
= xy is ---
A) Linear D. E. B) Homogeneous D. E.
C) Bernaoll‟s D. E. D) Non- homogeneous D. E.
22. The diff. Eq. (1 + xy) ydx + (1 - xy) xdy = 0
A) Not exact D. E. B) Clairaut‟s D. E.
C) Linear D. E. D) Non- homogeneous D. E.
24. The diff. Eq. 3
ଶ య
+ y = య
is ---
25.
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 37/46
Unit V
Differential Equations
Q-1. Questions 2 - Marks
1. Let f( D)y = X be the L.D.E. If x = 0 with constant coefficient. Then
i) f ( D)y = 0 is called ---
ii) f (D ) = 0 is called ---
2. If m1,m
2,− − −− −m
n are n distinct real roots of A.E. f(D) = 0 then G.S. of
the equation f(D)y = 0 is ---
3. If m1
= m2
two root of f(D) = 0, then C. F. of f(D)y = 0 is ---
4. If m1
= α + iβ and m2
= α − iβ are the complex roots of the f(D) = 0 , then
G.S. of f(D)y = 0 is ---
5. If f ( D) = ( D − m1)( D− m
2)− − −−− ( D− m
n) , then the G.S. of the L.D.E.
f(D)y = 0 is --- .
6. If d 2 y dy
+ 4 + 4 y = e2 x ,then what is its complementary function ?dx2 dx
7. If f ( D2 ) is polynomial in D2 with constant coefficients and
F(-a)2
≠ 0 then i)
ଵ
cosሺ ሻ ?
ሺమሻ
ii)ଵ
ሺమሻ sinሺ ሻ ?
8. If D = d
dx and f(D) is a polynomial in D with constant coefficients then
i)1
eax ×V = ? f ( D)
ii)1
×V = ?
f ( D)
where V is function of x .
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 38/46
i)
1cos(ax) = ?
( D2+ a2 )r
9.
ii)1
sin(ax) = ?( D2
+ a2 )
10. Let ( D2+ 4) y = cos2 x , find P.I.
11. If D = d
dx and f(D) is a polynomial in D with constant coefficients then .
ଵ
ሺሻ ௫ ? ,ሺሻ 0
12.
i)1
eax= ?
( D − a)r
ii) If f ( D) = ( D − a)rφ ( D) and φ (a) ≠ 0,then1
eax= ?
f ( D)
Q-2. Define the following
1. Linear differential equation with constant co-efficients of order n.
2. Associated D.E. and Auxillary equation.
3. Inverse Operator
4. Homogeneous Linear Differential equation of the order n.
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 39/46
1 2
1 2 3
1 2 3
1 2
x
x
− x
Q-3. Multiple choices
1. If d 2 y dy
− 2 + 4 y = e2 x is a linear differential equation ,then C.F. is ----dx2 dx
a)(c1 + c2 x)e
b)(c x + c x2 )e x
c)(c1
+ c2)e
d )none of these
2. If ( D3
+ 3 D2
+ 3 D +1) y = e− x
is a linear differential equation then C.F. is
a)(c x + c x + c x2)e
− x
b)(c + c x + c x2 )e− x
c)(c1
+ c2
+ c3 x)e
d )none of t hese
3. If ( D2
+ 2 D + 3) y = x− 2 x2
is a linear differential equation then C.F. is ---
a)e− x (c cos 2 x + c sin 2 x )
− xb)e
− x
+ (c1cos 2 x + c
2sin 2 x )
c)e (c1cos 2 x + ic
2sin 2 x )
d )none of these
4. If ( D2
+ 4) y = cos 2 x is a linear differential equation then C.F. is ------
a)c1cos 2 x + c
2sin 2 x
b)c1cos 2 x + ic
2sin 2 x
c)c1sin 2 x + ic
2cos 2 x
d)none of these
5. If ( D2
+ 2) = cos 2 x is a linear differential equation then P.I. is ------
a) x sin 2 x
2 2
b)sin 2 x
2
c) x sin 2 x
2
d) x cos 2 x
2
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 40/46
2
1 2
1 2
1 2
1 2 3 4
6. If x2 d y+ x
dy− 4 y = 0 is a homogeneous L.D.E.,then solution of L.D.E.
dx2 dx
is ------
a) y = c e2 z
+ c e−2 z
b) y = c e4 z+ c e −4 z
c) y = c e2 z+ c e2 z
d)none of these
7. If ( D2
+ 4)2 y = cos
2 x is a linear differential equation then C.F. is -------
a)(c1
+ c2) cos 2 x + (c
3 x + c
4 x) sin 2 x
b)(c1
+ c2 x) cos 2 x + (c
3+ c
4 x) sin 2 x
c)(c x + c x2 ) cos 2 x + (c x + c x2 ) sin 2 x
d)none of these
8. Ifd 2 y
+ 4 y = 0 is a linear differential equation then G.S. is -------
dx2
a) A cos 2 x + B sin 4 x
b) A cos 2 x + B sin 2 x
c) A sin 2 x + B cos 4 x
d )none of these
9. If ( D2 − 6 D +13) y = 0 is a linear differential equation then G.S. is -------
a)e3 x
( Acos 2 x + B sin 2 x)
b)e3 x
( Acos 4 x + B sin 4 x)
c)e3 x (cos 2 x + B sin 2 x)
d )none of these
10. If x2 ௬
- 3x௬
+ 4y = 0 is a homogeneous L.D.E. , then G.S. is ------ ௫మ ௫
i) (c1 + c2 log x) x2
ii) x3e
3x
iii) x e3z
iv) z2
ez
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 41/46
2
Q-4. Numerical Examples 04 Marks
1) Solve d 2 y dy − 5 + 6 y = 0
dx2 dx
d 3 y dy
2) Solve −13+
12 y=
0
dx3 dx
3) Solve d 3 y d 2 y dy + 2 + = 0
dx3 dx2 dx
d 2 y dy 4) Solve 2 + 5 −12 y = 0
dx2 dx
5) Solve d 4 y
+ 4 y = 0dx4
6) Solve d 2 y dy + 4 + 4 y = e2 x
dx
2
dx 7) Solve x2 d y
+ xdy
− 4 y = 0dx2 dx
8) Solve d 2 y
+ y = 0dx2
9) Solve ( D3 − 6 D2
+ 9 D) y = 0
10) Solve ( D4
+ 8 D2
+16) y = 0
11) Solve ( D−1)2( D
2+1) y = 0
12) Solve ( D2
+ 4) y = cos2 x
13) Solve d 2 y dy − 2 + y = e2 x
dx2 dx
14) Solve d 2 y dy − − 6 y = e x cosh 2 x
dx2 dx
15) Solve d 2 y dy − 3 + 2 y = e5 x
dx2 dx
16) Solve 4 d2 y dy
+ 4 − x
+ y = 4e 2
dx2 dx
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 42/46
17) Solve
d 2 y − 9 y = e2 x
+ x2
dx2
18) Solve d 2 y dy − 5 + 6 y = x
dx2 dx
19) Solve d 3 y d 2 y dy + − − y = cosh x
dx3
dx2
dx
20) Solve d 3 y
− y = (1+ e x )2
dx3
⎡ d 2 y dy ⎤
21) Solve + 4 + 4 y = e−2 x+ x2
⎢ dx2 dx
⎢ ⎣ ⎥
22) Solve d 3 y
+ 8 y = x4+ 2 x +1
dx3
23) Solve d 2 y dy − 2 + 5 y = x2
dx2 dx
24) Solve d 3 y d 2 y dy − 3 + 3 − y = 2 x3 − 3 x2
+1dx3
dx2 dx
25) Solve d 3 y d 2 y dy + 6 + 12 − 8 y = e−2 x
+ x2
dx3 dx2 dx
26) Solve d 4 y d 2 y + 8 +16 = cos2 x
dx4 dx2
27) Solve d 4 y
− a4 y = cos ax dx4
28) Solve d 4 y
+ y = sin x sin 2 x dx4
29) Solve d 3 y
+ y = cos 2 x dx3
30) Solve d 2 y dy + 3 + 2 y = sin e x
dx2
dx
31) Solve d 2 y dy − 2 + y = x sin x
dx2 dx
32) Solve ( D2 – 5D + 6 )y = e
3x
33) Solve ( D2
+13 D + 36) y = e−4 x
+ sinh x
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 43/46
34) Solve ( D3
+ 3 D2
+ 3 D +1) y = e− x
35) Solve ( D3 − 5 D2
+ 8 D− 4) y = e2 x
36) Solve ( D2 − 2 D +1) y = e
x
37) Solve ( D
2
− 4 D
+ 4) y
= sinh 2 x
38) Solve ( D3 − 4 D) y = 2cosh 2 x
39) Solve ( D3 − 5 D2
+ 8 D− 4) y = e2 x
+ 3e x
40) Solve ( D3
+ 3 D2
+ 2 D) y = x2
41) Solve ( D2
+ 2 D + 3) y = x− 2 x2
42) Solve ( D2 − D− 2) y = 1− 2 x− 9e
− x
43) Solve ( D3
+ 3 D2
+ 2 D) y = x2
+ 4 x + 8
44) Solve ( D2 − 4 D + 4) y = 8( x
2+ e
2 x)
45) Solve ( D2 − 3 D + 2) y = 2 x
2 − 9 x2+ 6 x
46) Solve ( D2 − 4 D + 3) y = 2cos x + 4 sin x
47) Solve ( D3
+ D2 − D−1) y = sin x
48) Solve ( D3+ D) y = sin 3 x
49) Solve ( D2
+ 4) y = cos2 x
50) Solve ( D4 −1) y = cos xcos 3 x
51) Solve ( D2
+ 4) y = sin 3 x + e x
+ x2
52) Solve ( D3
+ D) y = cos x
53) Solve ( D
2
−1) y=
10 sin
2
x
54) Solve ( D2
+1) y = 12 cos2 x
55) Solve ( D3 − D2 − 6 D) y = cos x + x
2
56) Solve ( D3 − D2 − D +1) y = cosh x + sin x
57) Solve ( D2 − 2 D + 2) y = x2e3 x
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 44/46
58) Solve ( D2 − 4 D + 3) y = e
xcos 2 x
59) Solve ( D2 − 6 D +13) y = e
3 xsin 2 x
60) Solve ( D2 − 2 D + 4) y = e x cos2 x
61) Solve ( D2 − 2 D +1) y = 4 e x
x2
62) Solve ( D2 −1) y = x
2cos x
63) Solve ( D2 −1) y = x
2sin x
64) Solve ( D4 −1) y = cos x cosh x
65) Solve ( D4 −1) y = e x cos x
x ⎛ x 3 ⎞ 66) Solve ( D3+1) y = e2 x sin x + e 2 sin
⎢ 2 ⎢ ⎝ ⎟
67) Solve ( D3 − 7 D− 6) y = e
2 x(1+ x
2)
68) Solve ( D4 − 2 D3 − 3 D2
+ 4 D + 4) y = e x x
2
69) Solve ( D2 −1) y = xsinh x
70) Solve ( D2 −1) y = xe
2 x
71) Solve ( D2
+1) y = xcos2 x
72) Solve ( D2
+ 4) y = xsin x
73) Solve ( D2 −1) y = x
2cos x
74) Solve ( D2
+1) y = xcos2 x
75) Solve ( D2
+ 2 D + 2) y = xcos x
76) Solve ( D2
+ 3 D + 2) y = xsin 2 x
77) Solve ( D2
+ D) y = (1+ e x
)−1
78) Solve ( D2
+ 5 D + 6) = e−2 x
sec2 x(1+ 2 tan x)
79) Solve ( D2 − 2 D +1) = xe
xsin x
80) Solve ( D2 − 9 D +18) y = e
e−3 x
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 45/46
81) Solve ( D2 + 3 D + 2 )y = sin ex
82) Solve ( D2 + 3 D + 2 )y =
83) Solve ( D2 + 4 )y = tan 2x
84) Solve ( D2 + 3 D + 2 )y = sin e -x
85) Solve ( D2
- 2 D + 2 )y = x ex
cosx
86) Solve ( D2
- 1 )y = ( 1 + e-x
)-2
87) Solve ( x2D2 + x D - 4 )y = 0
88) Solve ( x2D2 - 3x D + 4 )y = 2x2
89) Solve ( D2 – 1/x D + 1/x2 )y = (2/x2) Logx
90) Solve ( x2D2 - x D - 3 )y = x2 Logx
91) Solve ( x2D
2- 3x D + 5 )y = x
2sin (Logx)
92) Solve [( 2x+ 1 )2
D2 – 2 (2x + 1 ) D - 12 ]y = 6x
93) Solve [(1 + x)2D2 + ( 1 + x ) D + 1 ]y = 4 cos [ Log (2 + x ) ]
94) Solve ( x2D2 + 4x D + 2 )y = ex
95) Solve [( 2x- 1 )3 D3 + ( 2x- 1 ) D - 2 ]y = 0
96) Solve [( 3x+ 2 )2 D2 + 3 (3x + 2 ) D - 36 ]y = 3x2 + 4x + 1
97) Solve [( 1+x )2 D2 + (1+x ) D + 1 ]y = 2 sin[ log(1+x) ]
98) Solve [( x + 3 )2 D2 – 4 ( x + 3 ) D + 6 ]y = log ( x + 3 )
99) Solve [( x + 2 )2 D2 – ( x + 2 ) D + 1 ]y = 3x + 4
8/11/2019 F. Y. B. Sc. (Mathematics) Question Bank-II
http://slidepdf.com/reader/full/f-y-b-sc-mathematics-question-bank-ii 46/46
⎢
⎢
Q-5. Theory Questions 06 Marks
1) If D = d
dx and f(D) is a polynomial in D with constant coefficients ,then
Prove thatଵ
ሺሻ ௫
ଵ
ሺሻ ௫, ሺሻ 0
2) Prove that
1eax
=
( D − a)r
xreax
r!
r ax
Hence1
eax=
x e , if f ( D) = ( D − a)rφ ( D) & φ (a) ≠ 0
f ( D) r!φ (a)
3) If f ( D2) is polynomial in D2 with constant coefficients and f (−a
2) ≠ 0
then prove that1
cos(ax + b) =cos(ax +b)
f ( D2 ) f (−a2 )
4) If f ( D2) is polynomial in D2 with constant coefficients and f (−a
2) ≠ 0
then 1sin(ax + b) =
sin(ax +b)
f ( D2 ) f (−a2 )
1 (−1)r xr ⎛ r π ⎞5) Prove that cos ax = cos ax +
( D2+ a2 )r r !(2a)r
2
⎢ , r∈ N
⎝ ⎟
1 (−1)r
xr
⎛
r π
⎞6) Prove that sin ax = sin ax +
( D2+ a2 )r r !(2a)r
2
⎢ , r∈ N
7) If D = d
dx
⎝ ⎟
and f(D) is a polynomial in D with constant coefficients ,then
Prove that1
eaxV = eax 1V , where V is a function of x.
f ( D) f ( D + a)
8) If D = d
dx and f(D) is a polynomial in D with constant coefficients ,then
Prove that1
xV =⎡ x −
1 f '( D)
⎤ 1V ,
where Vis a function of x.
f ( D) ⎢
f ( D) ⎢
f ( D)⎣ ⎥
9) Define a homogeneous linear differential equations & explains the me thods