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Question
If sinA + cosA = `sqrt(2)` , prove that sinAcosA = `1/2`
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Solution
We Know , `(sinA + cosA)^2 = sin^2A + cos^2A + 2sinA.cosA`
Given , (sinA + cosA) = `sqrt(2)`
⇒ 2 = 1 + 2sinA.cosA
⇒ 2sinA.cosA = 1
⇒ sinA.cosA = `1/2`
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