Answer:
Explanation:
This is a quadratic and needs to be factored as such. When we factor, we get
cosx = 1/2 and cosx = -1. Refer to the unit circle to find all the angles that have a cosine of 1/2. Those would be in Q1 and Q4; namely, pi/3 and 5pi/3. The angle where the cosine is -1 is at pi.
