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Question
Prove the following identity :
`1/(tanA + cotA) = sinAcosA`
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Solution
`1/(tanA + cotA) = sinAcosA`
`1/(tanA + cotA)`
= `1/(sinA/cosA + cosA/sinA) = 1/((sin^2A + cos^2A)/(sinAcosA))`
= `1/(1/(sinAcosA)` (`Q sin^2A + cos^2A = 1`)
= sinA cosA
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