Question

Which of the following angles is not coterminal with the other three? Question 15 options: 231° 51° –129° 591°

Answer 1

51

Explanation

Given angles can break like this :

231 = 180 +51

51= 0+51

-129= -180+51

591= 360+180+51

so angles 231, -129 and 591 corresponds to the same terminal while 51 is not related to the particular quadrant . so 51 is not co-terminal with the other three angles .