9

Set 1: Function Notation (Advanced)

Explanation

Answer: D

PROBLEM

If f(x) = 3x + 5 and g(x) = 1x + 1, find g(f(4)).

If f(x) = 3x + 5 and g(x) = 1x + 1, find g(f(4)).

A.

21

B.

20

C.

15

D.

18

✓ Correct

Detailed Explanation

Choice D is the best answer. f(4) = 3(4) + 5 = 17. g(17) = 1(17) + 1 = 18

Why others are wrong:
A: 21 is incorrect because it does not satisfy the equation.
B: 20 is incorrect because it does not satisfy the equation.
C: 15 is incorrect because it does not satisfy the equation.