8 The equation of a curve is \(y = ( 2 x - 3 ) ^ { 3 } - 6 x\).
- Express \(\frac { \mathrm { d } y } { \mathrm {~d} x }\) and \(\frac { \mathrm { d } ^ { 2 } y } { \mathrm {~d} x ^ { 2 } }\) in terms of \(x\).
- Find the \(x\)-coordinates of the two stationary points and determine the nature of each stationary point.