Free ACT Math: Functions Questions and Answers 2

Question 1

If g(x) = 3x − 5, what is g⁻¹(x) (the inverse function)?

Accepted Answer

g⁻¹(x) = (x + 5)/3

Answer

g⁻¹(x) = 3x + 5

Answer

g⁻¹(x) = (x − 5)/3

Answer

g⁻¹(x) = x/3 − 5

Question 2

For the function h(x) = √(x − 4), what is the domain?

Accepted Answer

x ≥ 4

Answer

x > 4

Answer

x ≥ 0

Answer

All real numbers

Question 3

If f(x) = x² and g(x) = x + 3, what is (f ∘ g)(x)?

Accepted Answer

(x + 3)²

Answer

x² + 3

Answer

x³ + 3x²

Answer

(x² + 3)²

Question 4

A function f is defined as f(x) = |x − 2| + 1. What is the minimum value of f(x)?

Accepted Answer

1

Answer

0

Answer

2

Answer

3

Question 5

Which of the following represents a function?

Accepted Answer

{(1,2), (3,4), (5,6), (7,8)}

Answer

{(1,2), (1,3), (2,4), (3,5)}

Answer

{(2,3), (4,3), (2,5), (6,7)}

Answer

{(1,1), (2,2), (2,3), (3,4)}

Question 6

If f(x) = 4x − 1 and f(a) = 11, what is the value of a?

Accepted Answer

3

Answer

2.5

Answer

4

Answer

48