2 A curve has polar equation \(r = \cos \theta \sin 2 \theta\), for \(0 \leqslant \theta \leqslant \frac { 1 } { 2 } \pi\). Find
- the equations of the tangents at the pole,
- the maximum value of \(r\),
- a cartesian equation of the curve, in a form not involving fractions.