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Prove that cosecA-2 cot 2A cos A=2sinA....

Prove that `cosecA-2 cot 2A cos A=2sinA.`

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`co sec A-2 cot 2A cos A=(1)/(sin A)-(2cos 2A cosA)/(sin 2A)`
`=(1)/(sin A)-(2cos 2A cos A)/(2ssin A cos A)`
`(1)/(sin A)-(cos 2A)/(sinA)`
`=(1-cos 2A)/(sinA)`
`=(2sin^(2)A)/(sin A)`
`=2sinA`
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CENGAGE-TRIGONOMETRIC RATIOS AND TRANSFORMATION FORMULAS-Exercise 3.4
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