4. A curve \(C\) has parametric equations
$$x = \sin ^ { 2 } t , \quad y = 2 \tan t , \quad 0 \leqslant t < \frac { \pi } { 2 }$$
- Find \(\frac { \mathrm { d } y } { \mathrm {~d} x }\) in terms of \(t\).
The tangent to \(C\) at the point where \(t = \frac { \pi } { 3 }\) cuts the \(x\)-axis at the point \(P\).
- Find the \(x\)-coordinate of \(P\).
\section*{LU}