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