Question

Please help solve!
g(x) = 4x + 3
f(x) = 3x-4
Find (g o f)(5)

Answer 1

(g o f)(5) = 47

Explanation:

We are given a composite function:

g(x) = 4x + 3

f(x) = 3x - 4

We are supposed to find (g o f)(5), which really means g( f(x) ). So, we put the function of f(x) for every x in g(x), like this:

g(x) = 4x + 3

g( f(x) ) = 4(3x - 4) + 3

g( f(x) ) = 12x - 16 + 3

g( f(x) ) = 12x - 13

Now, we also need to evaluate for x = 5, like this:

g( f(5) ) = 12(5) - 13

g( f(5) ) = 47