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Ch 1 – Functions and Their Graphs• Different Equations for Lines• Domain/Range and how to find them• Increasing/Decreasing/Constant• Function/Not a Function• Transformations• Shifts• Stretches/Shrinks• Reflections
• Combinations of Functions• Inverse Functions
Ch 1 – Functions and Their Graphs1.1 Formulas for lines slope vertical
line
point- horizontal slope line
slope- parallel intercept slopes
general perpendicular form slopes
12
12
xx
yym
−−
=
( )1212 xxmyy −=−
bmxy +=
0=++ CByAx
ax =
by =
mm
1−=⊥
mm =||
1.2 Functions domain (input)
range (output)
),1[ ∞−
),3[ ∞−
inclusive [
exclusivealway - exclusive ( ∞
1.2 Functions Increasing/decreasing/constant
on x-axis only (from left to right)
( )∞− ,1
never ][
always )(
1.2 and 1.3 Functions Function or Not a Function?
Domain? ( )∞∞− ,
Range? ),3[ ∞−
y-intercepts? ( )1,0 −
x-intercepts? ( ) ( )0,5 and 0,1−
increasing? ( )∞,2
decreasing? ( )2,∞−
1.2 and 1.3 Functions Finding domain from a given function.
Domain = except:
x in the denominator x in radical
( )∞∞− ,
( )4
32 −
=x
xxf
Can’t divide by zero
( ) 2or 2;, :domain −≠∞∞− x
( ) 62 −= xxf
Can’t root negative062 ≥−x
[ )∞,3 :domain
1.4 Shifts (rigid)
( )2010 −=− xy
horizontalshift
vertical shift
( )2hxaky −=−
( )2210 −=− xy
( )2012 −=− xy
1.4 Stretches and Shrinks (non-rigid)
( )23 xy =
stretch
vertical
( )2xcy =
( )23
1xy =
( )23xy =
horizontal
shrink stretch
2
3
1⎟⎠
⎞⎜⎝
⎛= xy
shrink
1.4 Reflections
xy −=
In the x-axis
( ) xxh =
In the y-axis
xy −=
( ) ( )xfxh −= ( ) ( )xfxh −=
If negative can be move to other side, flipped on x-axis.If can’t, flipped on y-axis.
1.5 Combination of Functions
( )( ) ( )( )xgfxgf =o
( ) ( ) ( )( )2 find ,3 and 2 Give −=+= gfxxgxxf o
( ) ( ) 6232 −=−=−g
( )( ) ( ) 462 −=−=− fgf
1.5 Combination of Functions
( )( ) ( )( )xgfxgf =o
( ) ( ) ( )( )2 find ,2 and 4 Give −=−= fgxxgxxf o
( ) ( ) 6422 −=−−=−f
( )( ) ( ) 1262 −=−=− gfg
1.6 Inverse Functions
( )other.each of inverses are
functions e verify thand 42 inverse theFind −= xxf
( ) . and switch and with Replace 1. yxyxf
42 −= yx.for Solve 2. y
yx 24 =+
yx
=+24
( )2
4+=x
xg
( )( ) xxgf =o that Show
( )( ) 42
42 −⎟
⎠
⎞⎜⎝
⎛ +=
xxgf o
( )( ) 44 −+= xxgf o
( )( ) xxgf =o
Ch 2 – Polynomials and Rational Functions• Quadratic in Standard Form• Completing the Square• AOS and Vertex• Leading Coefficient Test• Zeros, Solutions, Factors and x-intercepts• Given Zeros, give polynomial function• Given Function, find zeros• Intermediate Value Theorem, IVT• Remainder Theorem• Rational Zeros Test• Descartes’s Rule• Complex Numbers• Fundamental Theorem of Algebra• Finding Asymptotes
Ch 2 – Polynomials and Rational Functions
2.1 Finding the vertex of a Quadratic Function
( ) 782 2 ++= xxxf
a
bx
2−=
1. By writing in standard form (completing the square)
2. By using the AOS formula€
f x( ) = 2 x 2 + 4x + 4( ) + 7 − 8
€
f x( ) = 2 x + 2( )2
−1
( ) 222
8−=−=x
( )1,2 −−
€
f x( ) = 2 −2( )2
+ 8 −2( ) + 7 17168 −=+−=
2.1 Writing Equation of Parabola in Standard Form
( )( ) form. standardin equation its write,3,-6
throughpasses and 2,1at ex with vertparabola aGiven
.for solve and form standard into and ,, Substitute akhyx
€
y = a x − h( )2
+ k
( ) 246 +=− a
a48 =−
2−=a €
y = −2 x −1( )2
+ 2( ) 2136 2 +−=− a
2.2 Leading Coefficient Test
Leading Coefficient aPositive Negative
Leading exponent nOdd
Even
( ) ...+= naxxf
2.2 Zeros, solutions, factors, x-intercepts
There are 3 zero (or roots),solutions, factors,and x-intercepts.
function theofsolution a is 2=x
function theof zero a is 2=x
( ) function theoffactor a is 2−x
( ) function theofintercept -an is 0,2 x
2.2 Zeros, solutions, factors, x-intercepts
Find the polynomial functions with the followingzeros (roots).
€
x = −1
2, 3, 3
If the above are zeros, then the factors are:
( ) ( )( )332
1−−⎟
⎠
⎞⎜⎝
⎛+= xxxxf
Can be rewritten as( ) ( )( )( )3312 −−+= xxxxf 912112 23 ++−= xxx
2.2 Zeros, solutions, factors, x-intercepts
Find the polynomial functions with the followingzeros (roots). 112,112,3 −+=x
Writing the zeros as factors:
€
f x( ) = x − 3( ) x − 2 + 11( )[ ] x − 2 − 11( )[ ]
Simplifying.
€
f x( ) = x − 3( ) x − 2( ) − 11[ ] x − 2( ) + 11[ ]
€
f x( ) = x − 3( ) x − 2( )2
−11[ ]
€
f x( ) = x − 3( ) x 2 − 4x + 4 −11[ ]
€
= x − 3( ) x 2 − 4x − 7[ ]
( ) 2157 23 ++−= xxxxf
2.2 Intermediate Value Theorem (IVT)
IVT states that when y goes from positive to negative,There must be an x-intercept.
2.3 Remainder Theorem
( ) ( ) ( ) remainder. theis then by divided is When kfkxxf −
( ) ( ) ?7583 offactor a 2 Is 23 −++=+ xxxxfx
9- 1 2 3
2- 4- 6-
7- 5 8 3 2- :dividion synthetic Using
( )( ) graph. on thepoint a bemust 9- 2,- Also,
factor. anot is 2 Therefore,
remainder theis 9
+
−
x
2.3 Rational Zeros Test
tcoefficien leading of factors
ermconstant t of factors ZerosRational ==
qp
( ) pqxxf n ++= ...
( ) .3832 of zeros rational possible theFind 23 +−+= xxxf
2
3,
2
1,3,1
2,1
3,1
2 of Factors
3 of Factors±±±±=
±±±±
=
Possible
2.3 Descartes’s Rule
( ) 4653 23 −+−= xxxxf
3201
3003
==
Count number of sign changes of f(–x) for number ofpositive zeros
+ – + – 1 2 3 = 3 or 1 positive zeros
( ) ( ) ( ) ( ) 4653 23 −−+−−−=− xxxxf
Count number of sign changes of f(–x) for number of negative zeros.
– – – – 0 negative zeros (+) (–) (i)
2.3 Complex Numbers
conjugate. itsby 53Multiply i−
Complex number = Real number + imaginary number
Treat as difference of squares.
( )( )ii 5353 +−
( ) ( ) ( ) 3425953 22 =−−=− i
2.3 Complex Numbers
. 24
53 form standardin Write
i
i
−+
i
i
i
i
24
24
24
53
++
⋅−+
( )416
1020612
−−
−++=
iii
i
10
13
10
1
20
262+=
+=
2.5 Fundamental Theorem of Algebra
A polynomial of nth degree has exactly n zeros.
( ) 345 xxxf += has exactly 4 zeros.
2.5 Finding all zeros
1. Start with Descartes’s Rule
( ) 8122 235 +−++= xxxxxf
2. Rational Zeros Test (p/q)
+ – i
2 1 2
0 1 4
8,4,2,11
8,4,2,1PRZ ±±±±=
±±±±±
=
3. Test a PRZ (or look at graph on calculator).( )
084211
84211
812210111
−
−
−−x
( )
08421
8421
11−x
( )
0401
802
842122
−−
−+x
42 +x
iix 2,2 −=
2.6 Finding Asymptotes
Vertical Asymptotes
Horizontal Asymptotes
( )...
...
+
+==
m
n
bx
ax
D
Nxf
mn <
Where f is undefined. Set denominator = 0
Degree larger in D, y = 0. BOBOO
Degree larger in N, no h asymptotes. BOTNN
Degrees same in N and D, take ratio of coefficients.
mn >
mn=
b
ay =
Ch 3 – Exponential and Log Functions
• Exponential Functions• Logarithmic Functions• Graphs (transformations)• Compound Interest (by period/continuous)• Log Notation• Change of Base• Expanding/Condensing Log Expressions• Solving Log Equations• Extraneous Solutions
Ch 3 – Exponential and Log Functions
3.1 Exponential Functions
( ) ( )hxfkxh −=−Same transformation as
If negative can be move to other side, flipped on x-axis.If can’t, flipped on y-axis.
( ) 23 1 −= −xxf Shifted 1 to right, 2 down.
( ) xxf 3−= Flipped on x-axis.
( ) xxf −= 3 Flipped on y-axis.
3.1 Compounded Interest
nt
n
rPA ⎟
⎠
⎞⎜⎝
⎛ += 1
A total of $12,000 is invested at an annual interest rate of 3%. Find the balance after 5 years if the interest is compounded (a) quarterly and (b) continuously.
000,12=P
yearper 03.0=ryearper times4=n
years 5=t
€
A = 12,000( ) 1+0.03( )
4( )
⎛
⎝ ⎜
⎞
⎠ ⎟
4( ) 5( )
21.934,13≈
rtPeA=
€
A = 12,000( )e 0.03( ) 5( ) 01.942,13≈
3.2 Logarithms
yax =
Used to solve exponential problems (when x is an exponent).
xy alog=
a
ba b log
loglog =
Change of base
3.3 Logarithms
yy
x444
3
4 loglog35log5
log −+=
Expanding Log Expressions
( ) ( )x
xxx
22lnln2ln2
+=−+
Condensing Log Expressions
3.4 Solving Logarithmic Equations
( ) 4223 =x
Solve the Log Equation
142 =x
x in the exponent, use logs
14ln2ln =x
14ln2ln =x
2ln
14ln
2ln
2ln=x 807.3≈x
3.4 Solving Logarithmic Equations
0232 =+− xx ee
Solve the Log Equation
( )( ) 012 =−− xx ee
( ) 02 =−xe ( ) 01 =−xe
2=xe
2lnln =xe
2ln=x 1ln=x
1lnln =xe
1=xe
0=
3.4 Solving Logarithmic Equations
43log2 5 =xSolve the Log Equation
23log5 =x
23log 55 5 =x
253 =x
3
25=x
3.4 Solving Logarithmic Equations
( ) ( ) xxx ln232ln2ln =−+−Solve the Log Equation
( )( ) 2ln322ln xxx =−−
( )( ) 2322 xxx =−−
22 672 xxx =+−
0672 =+− xx
( )( ) 016 =−− xx
1,6=x
( )( ) invalid=− 21ln
6=x