Question

Select the correct answer.

Consider these functions:
px) = 5x + 2
g(x) = x2 - 1
What is the value of g(4-1))?
A.
2
B.
00
C.
22
D.
48

Answer 1

g(f(-1)) = 48

Explanation:

given the following

f(x) = 5x² + 2

g(x) = x²-1

g(f(x)) = g(5x²+2)

Replace x with 5x² + 2 in g(x) as shown;

g(5x²+2) = (5x²+2))²- 1

g(f(x)) = (5x²+2))²- 1

g(f(-1)) = (5(-1)²+2))²- 1

g(f(-1)) = (5+2))²- 1

g(f(-1)) = (7)²- 1

g(f(-1)) = 49 - 1

g(f(-1)) = 48