Question

How to Solve this?? Please provide steps for remembrance.

Answer 1

When a problem asks $g\circ f$, it really means: $g(f(x))$

So, whenever you have a function say f(x), and you want to find f(1), you plug 1 wherever you see an x. This problem is no differen, except we're plugging in an f(x) wherever we see an x in g(x) to get:

$g(f(x))=f(x)^2+16 \implies\\ g(f(x))=(\sqrt{x})^2+16 \implies\\ g(f(x))=x+16$