SSC CGL 2021 PYQ — Question 67

SSC CGL - 23 Aug 2021 - Shift 3 • Quantitative Aptitude • Q67

If = 4sec θ, 0° <  θ < 90°, then the value of cotθ + cosec θ is :

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Correct answer: B

Explanation

The correct answer is option 2 i.e. √3

1/1+sinθ × (1 - sinθ/1 -sinθ ) + 1/1 - sinθ × (1 + sinθ/1 + sinθ)

(1 + sinθ /1 – sin2θ) + (1 – sinθ /1 – sin2θ) = 4secθ

(1 + sinθ /cos2θ) + (1 – sinθ /cos2θ) = 4secθ

(1 + sinθ + 1 – sinθ)/cos2 θ = 4secθ

2/cos2θ = 4secθ

2sec2θ = 4secθ

secθ = 2

θ = 60°

cotθ + cosecθ = cot60° + cosec60°

cotθ + cosecθ = (1/√3) + (2/√3)

cotθ + cosecθ = 3/√3 = √3