If $y=\tan ^{-1} x$ then $\frac{dy}{dx}$ at $y=\frac{\pi}{3}$ is equal to:
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → $\frac{1}{4}$
$\frac{dy}{dx}=\frac{1}{1+x^2}⇒\left.\frac{dy}{dx}\right]_{at\,y=\frac{\pi}{3}}$
$\tan^{-1}x=\frac{\pi}{3}⇒x=\sqrt{3}$
$\frac{dy}{dx}=\frac{1}{1+{\sqrt{3}}^2}$
$=\frac{1}{4}$