Question

What is the value of g(f(x)) when x = -2 if f(x) = x³

and g(x) =

2x+1
when x < 0

x²-1
when x>0

Answer 1

g(f(-2)) = -15

Explanation:

• f(x) = x³

Then

f(-2) = (-2)³ = -8

• When x = -2 → g(f(x)) = g(f(-2)) = g(-8)

Since -8 ≤ 0 then g(-8) = 2×(-8) + 1 = -16 + 1 = -15

Conclusion:

g(f(-2)) = -15