$\"\"$

The function is $\"\"$ .

Apply derivative with respect to $\"\"$ \ \

$\"\"$

$\"\"$ .

Apply second derivative on each side with respect to $\"\"$ .

$\"\"$ .

The Quotient rule of the derivative: $\"\"$ .

$\"\"$

substitute $\"\"$ in the function $\"\"$ .

$\"\"$

Substitute $\"\"$ in the function $\"\"$ .

$\"\"$ .

$\"\"$

$\"\"$ .