If $y=\sin^{-1}\sqrt{\frac{x}{x+1}}+sec^{-1}\sqrt{\frac{x+1}{x}}$, then $\frac{dy}{dx}$ is |
0 1 $\frac{1}{\sqrt{x+1}}$ $\frac{1}{\sqrt{x}}$ |
0 |
The correct answer is Option (1) → 0 Given: $y = \sin^{-1} \left( \sqrt{ \frac{x}{x+1} } \right) + \sec^{-1} \left( \sqrt{ \frac{x+1}{x} } \right)$ Observe that: $\sqrt{ \frac{x}{x+1} } = \cos \theta \quad \Rightarrow \quad \sqrt{ \frac{x+1}{x} } = \sec \theta$ So, define $\theta = \cos^{-1} \left( \sqrt{ \frac{x}{x+1} } \right)$ Then: $y = \sin^{-1}(\cos \theta) + \sec^{-1}(\sec \theta) = (\frac{\pi}{2} - \theta) + \theta = \frac{\pi}{2}$ Hence, $y$ is constant. $\Rightarrow \frac{dy}{dx} = 0$ |