$\"\"$

The function is $\"\"$ .

Find $\"\"$ .

First find the first partial derivative $\"\"$ .

$\"\"$ .

Differentiate partially with respect to $\"\"$ treating $\"\"$ and $\"\"$ as constant.

$\"\"$

$\"\"$ .

Substitute $\"\"$ and $\"\"$ .

$\"\"$

$\"\"$ .

$\"\"$

$\"\"$ .