Simplify the following expression.
cos2 30°+ cos2 40°+ cos2 50°+cos2 60°
Show answer & explanation
Correct answer: A
Explanation
The correct answer is option 1 i.e. 2
Given that
cos2 30°+ cos2 40°+ cos2 50°+cos2 60°
= (√3/2)2 + sin2 50°+ cos2 50° + (½)2
= (3/4) + 1 + (1/4)
= 8/4 = 2