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Question
Prove the following identity :
tanA+cotA=secAcosecA
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Solution
tanA+cotA=secAcosecA
Consider LHS = tanA + cotA
tanA + cotA = `sinA/cosA + cosA/sinA = (sin^2A + cos^2A)/(sinA.cosA)`
⇒ `tanA + cotA = 1/(sinA.cosA) = 1/sinA 1/cosA`
⇒ tanA + cotA = cosecA.secA = RHS
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