MCQ
If $\cos (x + y) = y\sin x,$ then ${{dy} \over {dx}} = $
- ✓$ - {{\sin (x + y) + y\cos x} \over {\sin x + \sin (x + y)}}$
- B${{\sin (x + y) + y\cos x} \over {\sin x + \sin (x + y)}}$
- C$\frac{{y\cos x - \sin (x + y)}}{{\sin x - \sin (x + y)}}$
- DNone of these