Question

cos of theta = -1/2

Answer 1

@campbella18 any idea about this ?

so you know that cos 60 = 1/2

than - 1/2 what degree of cosine will have ?

Answer 2

u see cos function is negative in 2 and 3 quadrants and the value of theta in this question can have many values

Answer 3

so u have to subtract or add 60 to 180 degrees to get the answer and then u can add 360degrees to your answer to get different valued of theta