The functions are $\"\"$ .

$\"\"$

Find f(x) as follows :

Let $\"\"$ and find its inverse function.

$\"\"$

Replace h(x) with y.

$\"\"$

Interchange x and y.

$\"\"$

Add 4 to each side.

$\"\"$

Divide each side by 2.

$\"\"$

Replace y with h^{- 1}(x) and consider only positive value because to find the solution.

$\"\"$

Multiply each side by 2.

$\"\"$

Subtract 4 from each side.

$\"\"$

Let $\"\"$

Check : $\"\"$ .

The function $\"\"$ .