Question

HELP ASAP PLEASE!!!!

If f(x)= x^2 and g(x)= 2x+3, what is f (g(x))?


A. 4x^2+9

B. x^2+2x+3

C. 2x^2+3

D. 4x^2+12x+9

Answer 1

D

Explanation:

Substitute x = g(x) into f(x)

f(2x + 3) = (2x + 3)² ← expand factors

f(g(x)) = (2x)² + 6x + 6x + 3² = 4x² + 12x + 9 → D