I've been trying to prove these pair of functions are inverses:
f(x) = sqrt(16-x^2) and g(x) = -sqrt(16-x^2)
using f(g(x)) = g(f(x)) = x
however when I do the working out it seems i get f(g(x)) = abs(x) BUT g(f(x)) = -abs(x) for some reason. I just did basic substitution n I've checked a few times but I can't seem to resolve this problem.
Could someone please help?