SSC CGL 2020 PYQ — Question 96

SSC CGL Tier II - Quant - 16 Nov 2020 • Quantitative Aptitude • Q96

The value of (tan2 A + cot2 A - 2) - sec2 A cosec2 A is :

Show answer & explanation

Correct answer: A

Explanation

The correct answer is option 1 i.e. -4

⇒ (tan2 A + cot2 A - 2) - sec2 A cosec2 A

⇒ (sin2A/cos2A  +  cos2A/sin2A - 2) - 1/sin2ACos2A

⇒ ((sin4A + cos4A - 2sin2Acos2A) /sin2Acos2A) - 1/sin2ACos2A

⇒ ((sin4A + cos4A - 2sin2Acos2A + 2sin2Acos2A - 2sin2Acos2A) /sin2Acos2A) - 1/sin2ACos2A

⇒ ((sin4A + cos4A + 2sin2Acos2A - 4sin2Acos2A ) /sin2Acos2A) - 1/sin2ACos2A

⇒(1 - 4sin2Acos2A - 1)/sin2ACos2A

⇒ -4.