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Question
Prove that `sqrt((1 + sin A)/(1 - sin A))` = sec A + tan A.
Solution
LHS = `sqrt((1+sinA)/(1-sinA))`
`=sqrt((1+sinA)/(1-sinA)xx(1+sinA)/(1+sinA)`
`=sqrt((1+sinA)^2/(1-sin^2A))=sqrt((1+sinA)^2/cos^2A)`
`=(1+sinA)/cosA`
= sec A + tan A = RHS
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