Differentiate each of the following w.r.t

Differentiate each of the following w.r.t $x$ :

If $\mathrm{y}=\tan ^{-1}\left\{\frac{\sqrt{1+x}-\sqrt{1-x}}{\sqrt{1+x}+\sqrt{1-x}}\right\}$. Prove that $\frac{d y}{d x}=\frac{1}{2 \sqrt{1-x^{2}}}$.