Question

Differentiate with respect to $x$.
$\sin x.\cos x$.

Answer 1

Let $y=\sin x.\cos x$

or, $y=\frac{1}{2}\times \sin 2x$.

Now differentiating both sides with respect to $x$ we get,

$\frac{dy}{dx}=\frac{1}{2}\times 2\times \cos 2x$

or, $\frac{dy}{dx}=\cos 2x$.