Find the degree measures of the angle whose cosine is - √3/2.

A. 50° + n times 360° and 30° + n times 360

B. 120 + n times 360 and 60 + n times 360

C. 120+n times 360 and 240 + n times 360

D. 150+n times 360 and 210 + n times 360

Given that the cosine of an angle is - √3/2, to solve the value of the angle. use the function inverse cosine or arccosine. so the value of the angle

A = arccosine (-√3/2)

A = 150 degrees

so the answer is D.

150 + n times 360 and 210 + n times 360