Assignment 2A: Combining Transformations SOLUTIONS

Name:
SOLUTIONS
Date:
Period:
Assignment2A:CombiningTransformations
Lippman/Rasmussen
Answer the following problems from your Lippman/Ras
mussen textbook with as much details,
explanations, and work that is appropriate.
1.5: 16, 2626-28, 56, 99.
16. Tables of values for f ( x ) , g ( x ) , and h( x) are given below. Write g ( x ) and h( x) as
transformations of f ( x ) .
x -2 -1 0 1 2
f(x) -1 -3 4 2 1
x -3 -2 -1 0 1
g(x) -1 -3 4 2 1
3(4) = 6(4 + 8),
x -2 -1 0 1 2
h(x) -2 -4 3 1 0
9(4) = 6(4) − 8
For the following, explain how the graph is a transformation of a toolkit function, then write an
equation for each function graphed.
26.
>(? ) = (? − 1) − 3
@
27.
>(? ) = √? + 3 − 1
28.
>(? ) = |? + 2| + 2
56. f ( x) = x 2 horizontally stretched by a factor of 3, then shifted to the left 4 units and down 3 units.
@
@
8
1
4
>(? ) = C (? + 4)E − 3 = C ? + E − 3
D
3
3
99. Suppose you have a function y = f ( x ) such that the domain of f ( x ) is 1 ≤ x ≤ 6 and the range
of f ( x ) is −3 ≤ y ≤ 5. [UW]
a. What is the domain of f (2( x − 3)) ?
Solutions on next page.
b. What is the range of f ( 2( x − 3)) ?
c. What is the domain of 2 f ( x) − 3 ?
d. What is the range of 2 f ( x) − 3 ?
e. Can you find constants B and C so that the domain of f ( B ( x − C )) is 8 ≤ x ≤ 9?
f. Can you find constants A and D so that the range of Af ( x ) + D is 0 ≤ y ≤ 1?
(a) This transformation will shift the graph horizontally to the right 3 units, and then
compress the graph horizontally by a factor of
L
@
. To find the domain boundaries we need
1 = 2(? − 3) → ? = 3.5
6 = 2(? − 3) → ? = 6
So, the new domain is D. N ≤ 4 ≤ O.
(b) The transformations applied to this function are horizontal shifts and stretches, which
don’t affect the range, since the range is concerned with the y-values. So the range is
unchanged.
(c) The transformations applied to this function are vertical shifts and stretches, which
don’t affect the domain, since the domain is concerned with the x-values. So the domain is
unchanged.
(d) This transformation will stretch the graph vertically by a factor of 2, and then shift the
graph vertically down 3 units. The range will experience the same changes. So, the stretch
changes the range to −6 ≤ Q ≤ 10, and then the shift changes the range to −R ≤ S ≤ T..
(e) We want to transform the domain 1 ≤ ? ≤ 6 into the domain 8 ≤ ? ≤ 9 using a
horizontal shift and a horizontal stretch. So, we need to find the numbers B and C that give us
8 when we subtract C from 1 and multiply by B, and that also give us 9 when we subtract C
from 6 and multiply by B . This can be represented as a system of equations: W(6 − X) = 9,
8
and W(1 − X) = 8. Solving this system gives Y = N , Z[\ ] = −DR. We can check that these
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constants are correct by applying these changes > C^ (? + 39)E to the original function with
the domain 1 ≤ ? ≤ 6, and we get a new domain of 8 ≤ ? ≤ 9, so it is correct.
(f) The original range of −3 ≤ Q ≤ 5 a span of 8, and the new range of 0 ≤ Q ≤ 1 has a span
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of 1. So the graph has to compress into _ of the space. After compressing it, the range
`
^
becomes − _ ≤ Q ≤ _. Now it is the right size, but not in the right location. To get it between 0
`
and 1, we need to move it up, shifting it vertically a distance of _, which is the same as adding
`
_
a
_
to the minimum and maximum. Now the range is _ ≤ Q ≤ _ which equals 0 ≤ Q ≤ 1. So, we
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`
8
D
applied a compression of is _ and a shift of _, so
o b = c and d = c.