7 A curve has parametric equations
$$x = 2 \sin t , \quad y = \cos 2 t + 2 \sin t$$
for \(- \frac { 1 } { 2 } \pi \leqslant t \leqslant \frac { 1 } { 2 } \pi\).
- Show that \(\frac { \mathrm { d } y } { \mathrm {~d} x } = 1 - 2 \sin t\) and hence find the coordinates of the stationary point.
- Find the cartesian equation of the curve.
- State the set of values that \(x\) can take and hence sketch the curve.