cos ( -1500°) =______________ A. 1/2 B. -1/2 C. √3/2 D. -√3/2

cos-1500deg-a-1-2-b-1-2-c-3-2-d-3-2

cos ( -1500°) =______________

A. 1/2

B. -1/2

C. √3/2

D. -√3/2

I have been asked this question during an interview.

This is a very interesting question from Trigonometric Functions topic in chapter Trigonometric Functions of Mathematics – Class 11

The correct answer is A. 1/2

Explanation: cos(-1500°) = cos(1500°) {cos(-x) = cos x}

= cos (4*360° + 60°) = cos 60° = 1/2. {cos (2nπ+x) = cos x}