SarkariPYQ

SSC CHSL 2021 PYQ — Question 62

SSC CHSL - 16 April 2021 - Shift 1 • Quantitative Aptitude • Q62

Back to paper

If A = 60º, then what is the value of (4 cos3 A - 3 cos A)?

Show answer & explanation

Correct answer: A

Explanation

The correct answer is Option 1 i.e. -1.

Given:

A = 60º

Concept Used:

cos60° = ½

Explanation:

According to the given question,

(4 cos3 A - 3 cos A)

⇒ 4 (½)3 - 3(½)

⇒ 48−32{4 \over 8} - {3 \over 2}

⇒ -1

Hence the required answer is -1.