Solve this following
Question:

Mark $(\sqrt{ })$ against the correct answer in the following:

If $y=\tan ^{-1}\left\{\frac{\cos x}{1+\sin x}\right\}$ then $\frac{d y}{d x}=$ ?

A. $\frac{1}{2}$

B. $\frac{-1}{2}$

C. 1

D. -1

Solution:

$\frac{\mathrm{dy}}{\mathrm{dx}}=-\frac{1}{2}$