If y= tan^-1((3 cos x-4 sin x)/(4 cos x+3 sin x))+2 tan^-1(x/(1+√(1-x^2))), then (d y)/(d x) at x=(√ 3)/2 is equal to:

If $\displaystyle y=\tan ^{-1}\left(\frac{3 \cos x-4 \sin x}{4 \cos x+3 \sin x}\right)+2 \tan ^{-1}\left(\frac{x}{1+\sqrt{1-x^2}}\right)$, then $\displaystyle \frac{d y}{d x}$ at $\displaystyle x=\frac{\sqrt{3}}{2}$ is equal to: