Question

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Answer 1

For this case we must find the inverse of the following function:

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

For them we follow the steps:

We change f (x) to y:

$y = x ^ 2-1$

We exchange variables:

$x = y ^ 2-1$

We solve for "y":

$y ^ 2-1 = x$

We add 1 to both sides of the equation:

$y ^ 2 = x + 1$

We apply square root to eliminate the exponent:

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

We change y by $f ^ {- 1} (x)$:

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

Answer:

Option D