cot(2x) = csc(2x) - tanx

I tried working with either side, but I couldn't get anywhere. Any help is appreciated!!

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- Jan 27th 2014, 05:22 PMsakonpure6Tough Trig Identity
cot(2x) = csc(2x) - tanx

I tried working with either side, but I couldn't get anywhere. Any help is appreciated!! - Jan 27th 2014, 05:36 PMromsekRe: Tough Trig Identity
- Jan 27th 2014, 05:45 PMSlipEternalRe: Tough Trig Identity
Start with the LHS.

Use the following identities:

$\displaystyle \begin{align*}\cot x & = \dfrac{\cos x}{\sin x} \\ \cos (2x) & = 1-2\sin^2 x \\ \dfrac{a-b}{c} & = \dfrac{a}{c} - \dfrac{b}{c}\\ \dfrac{1}{\sin x} & = \csc x \\ \sin(2x) & = 2\sin x \cos x \\ \dfrac{\sin x}{\cos x} & = \tan x\end{align*}$ - Jan 27th 2014, 05:47 PMSlipEternalRe: Tough Trig Identity
- Jan 27th 2014, 07:25 PMibduttRe: Tough Trig Identity