SSC CGL 2024 PYQ — Question 74

SSC CGL - 13 Sep 2024 - Shift 1 • Quantitative Aptitude • Q74

If sin31° = α\alpha then the value of cot59° is:

Show answer & explanation

Correct answer: B

Explanation

The correct answer is option 2 i.e.  α 1−α2{α\ \over \sqrt{1 - α^2}}.

Given that, sin31° = α\alpha

⇒ sin (90° - 59°) = α\alpha

⇒ cos59° = α\alpha

cos x = BHB \over H

⇒ B = α\alpha and H = 1

Using Pythagoras theorem, P2 = H2 - B2

⇒ P2 = 1 - α2\alpha^2

⇒ P = ​1−α2​\sqrt​{1 - \alpha^2} ​

Also, cot x = BPB \over P

Now, cot59° = α1−α2\alpha \over {\sqrt{1 - \alpha^2}}

Hence the required answer is α1−α2\alpha \over {\sqrt{1 - \alpha^2}}.