Math 8 Chapter 4: Functions

Given f(x) = 2x and
g(x) = x²+3 , find f(g(x)).

• x²+2x+3

• 4x²+3

• 2x²+3

• 2x²+6

Is the relation a function? Why?

• Yes, because the x-value 11 has two y-values pair with it.

• Yes, because each x-value has only one y-value paired with it.

• No, because the x-value 11 has two y-values pair with it.

• No, because each x-value has only one y-value paired with it.

Identify the domain of the following relation:

• -6, 14, 2, 28

• (-6,14), (0,32), (2,38), (4,44)

• -6, 0, 2, 4

• 14, 32, 38, 44

Given f(x)= -3x+7 and g(x)=2x² - 8, find f(g(x)).

• f(g(x))= -6x²+31

• f(g(x))= -6x²+24

• f(g(x))=18x²-84x+6

• f(g(x))=9x²-42x-1

f(x) = 3x + 10
g(x) = x - 2
Find (f∘g)(0)

• 16

• 4

• -4

• None of these.

Given f(x) = 3x + 10
and g(x) = x - 2
Find f(g(5))

• 19

• 23

• -10

• None of these.

Which option below is the same as (f∘g)(x) (How can you rewrite this)

• f(x)*g(x)

• f(g(x))

• g(f(x))

• (f*g)(x)

What is the domain of the graph shown?

f(x) = 3x + 10
g(x) = x - 2
Find g(f(-10))

• -42

• -26

• -18

• None of these.

Given f\left(x\right)=\sqrt{4x-4} and g\left(x\right)=3x+1, find \left(g\circ g\right)\left(x\right) in simplest form.