8 A curve passes through \(( 0,11 )\) and has an equation for which \(\frac { \mathrm { d } y } { \mathrm {~d} x } = a x ^ { 2 } + b x - 4\), where \(a\) and \(b\) are constants.
- Find the equation of the curve in terms of \(a\) and \(b\).
- It is now given that the curve has a stationary point at \(( 2,3 )\). Find the values of \(a\) and \(b\).