cot(2x) = csc(2x) - tanx
I tried working with either side, but I couldn't get anywhere. Any help is appreciated!!
Start with the LHS.
Use the following identities:
$\displaystyle \begin{align*}\cot x & = \dfrac{\cos x}{\sin x} \\ \cos (2x) & = 1-2\sin^2 x \\ \dfrac{a-b}{c} & = \dfrac{a}{c} - \dfrac{b}{c}\\ \dfrac{1}{\sin x} & = \csc x \\ \sin(2x) & = 2\sin x \cos x \\ \dfrac{\sin x}{\cos x} & = \tan x\end{align*}$