Question

If ƒ (7) = 22, thenf-¹(f(7)) = [?]

Answer 1

Remember the following property of invertible functions:

$f(x)=y\qquad\Leftrightarrow\quad f^{-1}(y)=x$

Then:

$f^{-1}(f(x))=x\qquad\forall x$

Then:

$f^{-1}(f(7))=7$

Therefore, the answer is: 7.