- (a) Given that
$$y = \arcsin x \quad - 1 \leqslant x \leqslant 1$$
show that
$$\frac { \mathrm { d } y } { \mathrm {~d} x } = \frac { 1 } { \sqrt { 1 - x ^ { 2 } } }$$
(b)
$$\mathrm { f } ( x ) = \arcsin \left( \mathrm { e } ^ { x } \right) \quad x \leqslant 0$$
Prove that \(\mathrm { f } ( x )\) has no stationary points.