Question

Find (fog)(x) and the domain

Answer 1

(fog)(x) = 2sqrt(x) + 3

Domain: x ∈ R, x>=0

Explanation:

(fog)(x) = f(g(x))

let f(a) = f(g(x))

f(a) = 2a+3 = 2(g(x)) + 3 = 2sqrt(x) + 3

To find domain, pick most restricting domain of the functions that make up the compound function.