The value of is equal to :
- (A)-1
- (B)✓ Correct
- (C)
- (D)
Answer: (B)
Solution
Using the sum-to-product formula and properties of cosine:
This can be evaluated using the identity for sum of cosines in arithmetic progression. The sum equals:
This can be evaluated using the identity for sum of cosines in arithmetic progression. The sum equals:
JEE Main · 2022 · 27 Jun 2022 · Shift 1 · Single correct option