Question

Let f(x) = 2x and g(x) = -x – 4.What is (gºf)(x)?

Answer 1

This problem is about function composition. That is one function inside another.

We need to find

$(g\circ f)(x)$

This indicates we have to substitute f(x) inside g(x), as follows.

$\begin{gathered} g(x)=-x-4 \\ g(f(x))=-(2x)-4=-2x-4 \end{gathered}$

Therefore, the composition is

$(g\circ f)(x)=-2x-4$