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Verify 2+2cot^2x=2cotxsecxcscx

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2+2\cot^2x=2\cot x\sec x\csc x\\\\L=2(1+\cot^2x)=2\left(1+(\cos^2x)/(\sin^2x)\right)=2\left((\sin^2x)/(\sin^2x)+(\cos^2x)/(\sin^2x)\right)\\\\=2\left((\sin^2x+\cos^2x)/(\sin^2x)\right)=2\left((1)/(\sin^2x)\right)=(2)/(\sin^2x)\\\\R=2\left((\cos x)/(\sin x)\right)\left((1)/(\cos x)\right)\left((1)/(\sin x)\right)=2\left((1)/(\sin x)\right)\left((1)/(1)\right)\left((1)/(\sin x)\right)\\\\=2\left((1)/(\sin^2x)\right)=(2)/(\sin^2x)


\boxed{L=R}


Used:\\\\\cot x=(\cos x)/(\sin x)\\\\\sin^2x+\cos^2x=1\\\\\sec x=(1)/(\cos x)\\\\\csc x=(1)/(\sin x)

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