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SSC CGL 2020 PYQ — Question 59

SSC CGL Tier II - Quant - 15 Nov 2020 • Quantitative Aptitude • Q59

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cosA(secA - cosA)(cotA + tanA) = ?

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Correct answer: A

Explanation

 The correct answer is option 1 i.e. tan A

Concept

1 – cos2A = sin2A

1 + tan2A = sec2A

Application

cosA(secA - cosA) (cotA + tanA)

(1 – cos2A) (1/tanA + tanA)

sin2A × (1 + tan2A)/tanA

sin2A × sec2A/tanA

tan2A / tanA

cosA (secA - cosA) (cotA + tanA) = tanA