SarkariPYQ

SSC CGL 2022 PYQ — Question 64

SSC CGL - 20 April 2022 - Shift 2 • Quantitative Aptitude • Q64

Back to paper

If tan2A - 6 tan A + 9 = 0, 0 < A < 90°, what is the value of 6 cot A + 810\sqrt{10}cosA?

Show answer & explanation

Correct answer: D

Explanation

The correct answer is option 4 i.e. 10

tan2A - 6tan A + 9 = 0

⇒ (tan A - 3)2 = 0

⇒ (tan A - 3) = 0

⇒ tan A = 3

So, P/B = 3/1

Now,

H2 = 32 + 12

⇒ H2 = 9 + 1

⇒ H2 = 10

⇒ H = (10)½

So, cos A = 1/(10)½

Now,

6 cot A + 8 (10)½ cot A = 6 × (1/3) + 8 (10)½ × (1/10)

⇒ 2 + 8

⇒ 10