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Sin A + cos A÷sinA - cosA+sinA-cosA÷ sinA+cosA = 2÷ 1- cos²A |
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Answer» sinA−cosA sinA+cosA
+ sinA+cosA sinA−cosA
= (sinA−cosA)(sinA+cosA) (sinA+cosA)
+ (sinA−cosA)(sinA+cosA) (sinA−cosA) 2
= sin 2 A−COS 2 A sin 2 A+cos 2 A+2sinAcosA+sin 2 A+cos 2 A−2sinAcosA
= sin 2 A−cos 2 A 2
= sin 2 A−(1−sin 2 A) 2
= 2sin 2 A−1 2
= 2(1−cos 2 A)−1 2
= 1−2co View solution Prove that sin(A+B+C)+sin(−A+B+C)−sin(A−B+C)+sin(A+B−C) cos(A+B+C)+cos(−A+B+C)+cos(A−B+C)+cos(A+B−C)
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