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SSC CGL 2018 PYQ — Question 51

SSC CGL Tier II Quant - 21/02/2018 • Quantitative Aptitude • Q51

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What is the value of [2 cot (π – A)/2]/[1 + tan2 (2π – A)/2]?

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Correct answer: C

Explanation

The correct answer is option 3 i.e. sin A

[2 cot(π - A)/2]/[1 + tan2(2π - A)/2]

= [2cot(π/2 - A/2)]/[1 + tan2(π - A/2)]

= 2tan (A/2)/[1 + tan2(A/2)]

= sin A (∵ 2tan2x/(1 + tan2x) = sin2x)