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Question
Prove the following trigonometric identities
(1 + cot2 A) sin2 A = 1
Solution
We know that `cosec^A - cot^2 A = 1`
So,
`(1 + cot^2 A)sin^2 A = cosec^2 A sin^2A`
`= (cosec A sin A)^2`
`= (1/sin A xx sin A)^2`
`= (1)^2`
= 1
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