SSC CGL 2020 PYQ — Question 30

SSC CGL Tier II - Quant - 16 Nov 2020 • Quantitative Aptitude • Q30

 secA(secA+tanA)(1−sinA)(cosec2A−1)sin2A\frac{sec A(sec A + tan A)(1 - sin A)}{(cosec^2 A-1)sin^2 A}is equal to:

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Correct answer: C

Explanation

The correct answer is option 3 i.e. sec2 A.

On solving the numerator part first,

= SecA(SecA + TanA)(1 - SinA)

= 1/CosA(1/CosA + SinA/CosA)(1 - SinA)

= (1 + SinA)/Cos2A × (1 - SinA)

= 1.

Now solve the denominator part,

= (Cosec2A - 1)Sin2A 

= (1 - Sin2A)

= Cos2A

On combining,

= 1/Cos2A

= Sec2A