SSC CGL 2022 PYQ — Question 72

SSC CGL - 20 April 2022 - Shift 1 • Quantitative Aptitude • Q72

Simplify the following expression:

cosec4A(1 - cos4A) - 2cot2A - 1

Show answer & explanation

Correct answer: B

Explanation

The correct answer is option 2 i.e. 0

Formula used:

sin2A + cos2A = 1

cosec2A - cot2A = 1

Calculations:

⇒ cosec4A(1 - cos4A) - 2cot2A - 1

⇒ cosec4A((1 - cos2A)(1 + cos2A)) - cot2A - (cot2A + 1)

⇒ cosec4A(sin2A × (1 + cos2A)) - cot2A - cosec2A

⇒ cosec2A × (1 + cos2A) - cot2A - cosec2A

⇒ cosec2A + cot2A - cot2A - cosec2A

⇒ 0