Question

Assume that f is a one-to-one function. (a) if f(1) = 12, what is f −1(12)

Answer 1

As it is one-to-one function, f −1(12) = 1

Answer 2

f-1(x)  is the inverse of f(x)

The domain of f(x) = range of f(-1)x  and vice-versa.

So f-1(12)  = 1.