$\"\"$

The expression is $\"\"$ .

$\"\"$ (Multiply numerator and denominator by the conjugate $\"\"$ ) \ \

$\"\"$ (Apply distributive property: $\"\"$ )

$\"\"$ (Product of sum and difference property: $\"\"$ )

$\"\"$ (Evaluate powers: $\"\"$ and $\"\"$ )

$\"\"$ (Subtract: $\"\"$ )

$\"\"$ .

Therefore, the simplified expression is $\"\"$ . $\"\"$

$\"\"$ .