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Prove the following: cos (3π/2 +x) cos (2π+x) [cot(3π/2-x)+ cot (2π+x)] |
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Answer» L.H.S. = cos (3π/2 +x) cos (2π+x) .[cot(3π/2-x)+ cot (2π+x)] = (sin x)(cos x) (tan x + cot x) = sin x cos x (\((\frac{sin\, x}{cos\, x} + \frac{cos\, x}{sin\,x})\)) = sin x cos x \((\frac{sin^2\, x+cos^2\, x}{sin\,x\,cos\,x})\) = sin x cos x (\(\frac{1}{sin\, x\, cos\, x}\)) = 1 = R.H.S |
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