Question

Theta -90 90 Cosine (theta) ? 0 a. 1 c. 2 b. -1 d. 0

Answer 1

b. -1.

Explanation:

The cosine function is periodic with period 2π, and for angles in the range [-90°, 90°], it takes on values in the range [-1, 1].

For the angle θ = -90°, the cosine is given by:

cos(-90°) = cos(270°) = -1

the answer is b. -1.