4 The function f is defined for all real values of \(x\) by
$$\mathrm { f } ( x ) = x ^ { 3 } + x$$
- Express \(\mathrm { f } ( 2 + h ) - \mathrm { f } ( 2 )\) in the form
$$p h + q h ^ { 2 } + r h ^ { 3 }$$
where \(p , q\) and \(r\) are integers.
- Use your answer to part (a) to find the value of \(\mathrm { f } ^ { \prime } ( 2 )\).