SSC CHSL 2023 PYQ — Question 65

SSC CHSL - 09 Aug 2023 - Shift 2 • Quantitative Aptitude • Q65

If cot A= 512\frac{5}{12}, find the value of the following expression.

5(1−cos2A)6(1−sin2A)\frac{5(1-cos^2 A)}{6(1-sin^2 A)}

Show answer & explanation

Correct answer: D

Explanation

The correct answer is option 4 i.e. 245\frac{24}{5}.

cot A = Base/Length = 5/12

Hypotenuse = √(52 + 122) = √(25 + 144) = √169 = 13

Now, 5(1−cos2A)6(1−sin2A)\frac{5(1-cos^2 A)}{6(1-sin^2 A)}

= [5(1 - (5/13)2)]/[6(1 - (12/13)2)]

= [5(1 - 25/169)]/[6(1 - 144/169)]

= [5(144/169)]/[6(25/169)]

= 720/150

= 24/5

Therefore, the value of the expression is 24/5.