SSC CGL 2021 PYQ — Question 65

SSC CGL - 13 Aug 2021 - Shift 1 • Quantitative Aptitude • Q65

cosec θcosec θ−1+cosec θcosec θ+1−tan2 θ\frac{cosec \ \theta}{cosec \ \theta - 1}+\frac{cosec \ \theta}{cosec \ \theta + 1}-tan^2 \ \theta, 0º < Θ < 90º, is equal to:

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Correct answer: A

Explanation

The correct answer is option 1 i.e. sec2 Θ + 1

cosec θcosec θ−1+cosec θcosec θ+1−tan2 θ\frac{cosec \ \theta}{cosec \ \theta - 1}+\frac{cosec \ \theta}{cosec \ \theta + 1}-tan^2 \ \theta

cosec θ(cosec θ+1)+cosec θ(cosec θ−1)cosec2 θ − 1−tan2 θ\frac{cosec \ \theta(cosec \ \theta+1)+cosec \ \theta(cosec \ \theta-1)}{cosec^2 \ \theta \ - \ 1}-tan^2 \ \theta

2cosec2 θcosec2 θ − 1−tan2 θ\frac{2cosec^2 \ \theta}{cosec^2 \ \theta \ - \ 1}-tan^2 \ \theta

2cosec2 θcot2 θ−tan2 θ\frac{2cosec^2 \ \theta}{cot^2 \ \theta}-tan^2 \ \theta

2sec2 θ−tan2 θ2sec^2 \ \theta-tan^2 \ \theta

2sec2 θ−sec2 θ+12sec^2 \ \theta-sec^2 \ \theta + 1

sec2 θ+1sec^2 \ \theta + 1