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Verify
(2cos2x)/(sin2x) - cotx - tanx = -2tanx

User Hyubs
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1 Answer

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Remember:


\boxed{sin(2x)=2.sinx.cosx}\\ \\ and\\ \\ \boxed{cos(2x)=cos^2x-sin^2x}



(2cos2x)/(sin2x)-cotx-tanx=\\ \\ (2(cos^2x-sin^2x))/(2sinx.cosx)-(cosx)/(sinx)-(sinx)/(cosx)=\\ \\ (cos^2x-sin^2x)/(sinx.cosx)-(cosx)/(sinx)-(sinx)/(cosx)=\\ \\ (cos^2x-sin^2x-cos^2x-sin^2x)/(sinx.cosx)=\\ \\ (-2sin^2x)/(sinx.cosx)=\\ \\ (-2sinx)/(cosx)=-2.tanx
User Jason Sundram
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