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If cosA + sinA= root2 cosA, show that cosA - sinA=root2 sinA |
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Answer» In given take cosA to rhs take common, and then whatever you will get take, it to lhs again now rationalize the denominator and solve yu will get the proof............? CosA +sinA =\xa0√2cosAsquaring⇒(cosA + sin A)² = (√2cosA)²⇒cos²A + sin²A\xa0+ 2sinAcosA = 2cos²A⇒1\xa0-\xa0sin²A\xa0+ 1 -\xa0cos²A\xa0+ 2sinAcosA\xa0= 2cos²A⇒2 - 2cos²A =\xa0cos²A + sin²A -\xa02sinAcosA\xa0⇒2(1 - cos²A)= (cosA - sinA)²⇒\xa0cosA - sinA =\xa0√[2sin²A]⇒cosA-sinA =\xa0√2sinA |
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