SarkariPYQ

SSC CGL 2022 PYQ — Question 70

SSC CGL - 06 Dec 2022 - Shift 4 • Quantitative Aptitude • Q70

Back to paper

What is the value of cos215°?

Show answer & explanation

Correct answer: B

Explanation

The correct answer is option 2 i.e.  (2+√3)4{{(2+√3)} \over 4}.

Cos 15° = 3+122\frac{\sqrt3+1}{2\sqrt2}

So,  cos215° = 3+122\frac{\sqrt3+1}{2\sqrt2} × 3+122\frac{\sqrt3+1}{2\sqrt2}

= (2+√3)4{{(2+√3)} \over 4}