Question

If ƒ(x) = 4x² and g(x) = 5x, what is g(ƒ(2x)) ?

Answer 1

Given $f(x)=4x^2,g(x)=5x$. Now

$f(2x)=4(2x)^2=16x^2$.

Thus,

$g(f(2x))=5f(2x)\\ g(f(2x))=5*16x^2\\ g(f(2x))=80x^2$