Question

Which function below is the inverse of f(x) = x2 − 16?

Answer 1

$f(x) = x^{2} - 16$
$y = x^{2} - 16$
$x = y^{2} - 16$
$x + 16 = y^{2}$
$\±\sqrt{x + 16} = \sqrt{y^{2}}$
$\±\sqrt{x + 16} = y$
$\±\sqrt{x + 16} = f^{-1}(x)$