4 A curve has parametric equations
$$x = 2 \sin 2 t , \quad y = 3 \cos 2 t$$
for \(0 < t < \frac { 1 } { 2 } \pi\). For the point on the curve where \(t = \frac { 1 } { 3 } \pi\), find the value of
- \(\frac { \mathrm { d } y } { \mathrm {~d} x }\),
- \(\frac { \mathrm { d } ^ { 2 } y } { \mathrm {~d} x ^ { 2 } }\).