Question

Solve the problem.Find (g ∘ f)(2) when f(x) = and g(x) = 4x2.

Answer 1

In order to calculate (gof)(2), first let's calculate f(2), then we use the result as the value of x for g(x).

So we have:

$\begin{gathered} f(x)=\sqrt{2x+5}\\ \\ f(2)=\sqrt{4+5}\\ \\ f(2)=3\\ \\ \\ \\ g(x)=4x^2\\ \\ g(f(2))=g(3)=4\cdot3^2\\ \\ g(f(2))=36 \end{gathered}$