Core Connections Integrated II, 2015
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Core Connections Integrated II, 2015 View details
3. Section 9.3
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Exercise 81 Page 512

Practice makes perfect
a Using the function f(x), we want to find the expression a(x) = f(x)-2. To do this, we will subtract 2 from the given function and simplify.
f(x)=x^2-3
f(x)- 2=x^2-3- 2
f(x)-2=x^2-5

Therefore, the transformed function a(x) is given by the following formula. a(x) = x^2-5 Vertical translations occur when we add or subtract a value from the output of a function. We can observe it more clearly in the table below.

Vertical Translations
Translation up k units, k>0 y=f(x)+ k Translation down k units, k>0 y=f(x)- k

We can describe our transformation as vertical translation 2 units down. It means that the graph of the given function was shifted 2 units down.

b Using the function f(x), we want to find the expression b(x) = - 2 * f(x). To do this, we will multiply the given function by - 2 and simplify.
f(x)=x^2-3
- 2 * f(x)= - 2(x^2-3)
- 2 * f(x)=- 2x^2+6

Therefore, the transformed function b(x) is given by the following formula. b(x) = -2x^2+6 Let's name our transformation using the table below.

Reflections
In the x-axis y=- f(x) In the y-axis y=f(- x)
Vertical Stretch or Shrink
Vertical stretch, a>1 y=af(x) Vertical shrink, 0

We can describe our transformations as a reflection in the x-axis and a vertical stretch by a factor of 2.

c Using the function f(x), we want to evaluate for the given value, c(x) = f( x-2). To do this, we need to substitute x-2 for x in each instance of the x-variable.
f(x)=x^2-3
f( x-2)=( x-2)^2-3

Therefore, the transformed function c(x) is given by the following formula. c(x) = (x-2)^2-3 Horizontal translations occur when we add or subtract a value from the input of a function. We can observe it more clearly in the table below.

Horizontal Translations
Translation right h units, h>0 y=f(x- h) Translation left h units, h>0 y=f(x+ h)

We can describe this transformation as horizontal translation 2 units right. It means that the graph of the given function was shifted 2 units right.

d Using the function f(x), we want to evaluate for the given value, d(x) = f( 2x). To do this, we need to substitute 2x for x in each instance of the x-variable and simplify.
f(x)=x^2-3
f( 2x)=( 2x)^2-3
f(2x)=2^2x^2-3
f(2x)=4x^2-3

Therefore, the transformed function d(x) is given by the following formula. d(x) = 4x^2-3 Let's name our transformation using the table below.

Horizontal Stretch or Shrink
Horizontal stretch, 0 Horizontal shrink, b>1 y=f(bx)

We can describe our transformation as a horizontal stretch by a factor of 2.