$\"\"$

The function is $\"\"$ .

Apply logarithm on each side.

$\"\"$

Power property of logarithms : $\"\"$ .

$\"\"$ .

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

$\"\"$

Product rule of derivative: $\"\"$ .

$\"\"$

Substitute $\"\"$ in above equation.

$\"\"$ .

$\"\"$

$\"\"$ .