Question

Find $\frac{dy}{dx},$ if $y=\sqrt{cos(3x+1)}$

Answer 1

If $y=\sqrt{\cos (3x+1)}$

then

$\frac{dy}{dx}=\frac{d}{dx}\sqrt{\cos (3x+1)}$

$\frac{dy}{dx}=\frac{1.(-(\sin 3x+1)\times 3)}{2\sqrt{\cos (3x+1)}}$

$\frac{dy}{dx}=-\frac{3}{2}\frac{\sin (3x+1)}{\sqrt{\cos (3x+1)}}$.