$\"\"$

The expression is $\"\"$

$\"\"$ (Product of two different signs is negative)

$\"\"$ ( $\"\"$ ) $\"\"$

if $\"\"$ ,where b,d $\"\"$

$\"\"$

$\"\"$ (Cancel common terms)

$\"\"$ (Multiply numerators: $\"\"$ )

$\"\"$ (Multiply denominators: $\"\"$ )

$\"\"$

The product is $\"\"$ .