Given the following functions:
f(x) = 3x
g(x) = x + 4
h(x) = x^2 - 1
Before simplifying g(f(-1)), let's first determine f(-1).
f(-1) = 3(-1)
f(-1) = -3
g(f(-1)) = (-3) + 4
= -3 + 4
g(f(-1)) = 1
Therefore, the answer is 1.
