Question

Help me answer this question please

Answer 1

ANSWER

${f}^{ - 1} =\pm \sqrt{x + 1}$

EXPLANATION

The given function is

$f(x) = {x}^{2} - 1$

Let

$y = {x}^{2} - 1$

Interchange x and y to get:

$x= {y}^{2} - 1$

Solve for y,

$x + 1 = {y}^{2}$

Take square root of both sides to get,

$\pm \sqrt{x + 1} = y$

This is the same as:

$y = \pm \sqrt{x + 1}$

Therefore the inverse is

${f}^{ - 1} =\pm \sqrt{x + 1}$