Find $\int \frac{dx}{\sqrt{\sin^3 x \cos(x - \alpha)}}$. |
$-2 \frac{\sqrt{\cot x \cos \alpha + \sin \alpha}}{\sqrt{\cos \alpha}} + c$ $\frac{\sqrt{\cot x \cos \alpha + \sin \alpha}}{\cos \alpha} + c$ $-2 \frac{\sqrt{\cot x \cos \alpha + \sin \alpha}}{2\sqrt{\cos \alpha}} + c$ $\frac{\sqrt{\cot x \cos \alpha + \sin \alpha}}{2\sqrt{\cos \alpha}} + c$ |
$-2 \frac{\sqrt{\cot x \cos \alpha + \sin \alpha}}{\sqrt{\cos \alpha}} + c$ |
The correct answer is Option (1) → $-2 \frac{\sqrt{\cot x \cos \alpha + \sin \alpha}}{\sqrt{\cos \alpha}} + c$ $\int \frac{dx}{\sqrt{\sin^3 x \cos(x - \alpha)}}=\int \frac{dx}{\sqrt{\sin^3 x (\cos x \cos \alpha + \sin x \sin \alpha)}}$ $= \int \frac{dx}{\sin^2 x \sqrt{\frac{\cos x}{\sin x} \cos \alpha + \sin \alpha}}$ $= \int \frac{\text{cosec}^2 x \, dx}{\sqrt{\cot x \cos \alpha + \sin \alpha}}$ $=\frac{1}{\sqrt{\cos \alpha}}\int \frac{\text{cosec}^2 x \, dx}{\cot x+\tan \alpha}$ Let $\cot x +\tan \alpha=t$ $-\text{cosec}^2 x dx=dt$ $= \frac{1}{\sqrt{\cos \alpha}} \int \frac{-dt}{\sqrt{t}}$ $= -\frac{2\sqrt{t}}{\sqrt{\cos \alpha}} + c$ $=-2 \frac{\sqrt{\cot x \cos \alpha + \sin \alpha}}{\sqrt{\cos \alpha}} + c$ |