If f(2)=6 find f^-1(6)

Answer 1

When you see f^-1(x), what that really means is the problem is asking you "f of what is equal to x?" For instance, if f(x)=a, we know f^-1(a) is really asking "f of what is a?" and we saw before that f(x)=a, so f^-1(a)=x! Therefore, if f(2)=6, f^-1(6)=2!