$$\displaystyle\frac{d}{d x } \left( { e }^{ \sqrt{ 1- { x }^{ 2 } } } \right)$$
$-\frac{xe^{\sqrt{1-x^{2}}}}{\sqrt{1-x^{2}}}$
$\frac{\left(-x^{4}+x^{2}-\sqrt{1-x^{2}}\right)e^{\sqrt{1-x^{2}}}}{\left(1-x^{2}\right)^{2}}$
