# How do you prove #(2 cos 3x)/(sin 4x - sin 2x)=cscx?

f(x) = $\frac{2 \cos 3 x}{\sin 4 x - \sin 2 x}$
$f \left(x\right) = \frac{2 \cos 3 x}{2 \cos 3 x . \sin x}$ = $\frac{1}{\sin} x$ = csc x