Question

Answer this question please

Answer 1

If a function is a one-to-one relation, then it is invertible. We have

$f(x) = y \iff f^{-1}(y)=x$

So, given

$f(3)=2,\quad f(-4)=8$

we can deduce

$f^{-1}(2)=3,\quad f^{-1}(8)=-4$