Grade 11 · Math
Compose two functions practice
Evaluate an inner function and use its result as the input of an outer function.
Opening your practice adventure…
Try a sample
Let f(x) = 5x + (4) and g(x) = x2. Find f(g(-4)).
- 82
- 84
- 83
- 88
See the answer & why
84
First g(-4) = (-4)2 = 16. Then f(16) = 5 × 16 + (4) = 84.
A little hint: Evaluate the inner function first; use its output as the input of the outer function.
A teaching tip
Read f(g(x)) from the inside out; function composition is not multiplication.