$\"\"$

(a)

The function is $\"\"$ , $\"\"$ and $\"\"$ .

Consider $\"\"$ .

Differentiate on each side with respect to $\"\"$ .

$\"\"$

Quotient rule of derivatives: $\"\"$ .

$\"\"$

Hence, $\"\"$ .

The differential function is $\"\"$ .

$\"\"$

(b)

The differential function is $\"\"$ .

Substitute $\"\"$ and $\"\"$ in above function.

$\"\"$

$\"\"$ .

$\"\"$

(a) The differential function is $\"\"$ .

(b) $\"\"$ .