The family of coterminal angles of 780 degree is given by th

The family of coterminal angles of -780 degree is given by the equation theta_c = -780 degree + K360 degree, K integer. The least positive coterminal angle of -780 degree is given when (a) K = -1 (b) K = -2 (c) K = 2 (d) K = 3 (e) K = 5

Solution

least positive coterminal of -780= 1080-780=300

so when k=3, we get theta=-780+3*360=300°

hence the correct option is d.