求曲线$\begin{cases}y = \sin t\\x = t^{2}\end{cases}$（$t$为参数）在$t = \dfrac{\pi}{3}$对应点处的切线方程.

求不定积分：$\int\sin\dfrac{x}{2}dx$.

若$f(x)=\sin x + x^{666}$，求$f^{(888)}(x)$.