$\"\"$

The function is $\"f$

c) $\"h$

$\"h$ ( $\"f$ )

$\"h$ (Take out $\"x$ term)

$\"h$ (Cancel common term nominator and denominator) $\"\"$

$\"italic$ (Take limits)

$\"italic$ (Simplify)

$\"italic$ (Proparty of limits)

$\"italic$ (Simplify)

$\"\"$

Therefore $\"italic$ .