SSC Selection Post 2020 PYQ — Question 53

SSC Selection Post - Graduation Level 2020 - 10 Nov 2020 - Shift 3 • Quantitative Aptitude • Q53

If (cos2θ - 1)(2sec2θ) + sec2θ + 2tan2θ = 2, 0° < θ < 90°, then (secθ+sinθ)(cosecθ−cosθ)(secθ + sinθ)\over (cosecθ - cosθ)  is equal to:

Show answer & explanation

Correct answer: D

Explanation

The correct answer is Option 4 i.e. 3.

(cos2θ - 1)(2sec2θ) + sec2θ + 2tan2θ = 2

⇒ (-sin2θ).2sec2θ + sec2θ + 2tan2θ = 2

⇒ -2tan2θ + 1 + tan2θ + 2tan2θ = 2

⇒ tan2θ = 1

⇒ θ = 45°

Now, (secθ + sinθ)/(cosecθ - cosθ)

= (sec45° + sin45°)/(cosec45° - cos45°)

= (√2 + 1/√2)/(√2 - 1/√2)

= (3/√2)/(1/√2)

= 3