1 The polynomial \(\mathrm { f } ( x )\) is defined by \(\mathrm { f } ( x ) = 15 x ^ { 3 } + 19 x ^ { 2 } - 4\).
- Find \(\mathrm { f } ( - 1 )\).
- Show that \(( 5 x - 2 )\) is a factor of \(\mathrm { f } ( x )\).
- Simplify
$$\frac { 15 x ^ { 2 } - 6 x } { f ( x ) }$$
giving your answer in a fully factorised form.