Question

which of the following angles is not coterminal with the other three? a. 591° b. 231° c. 51° d. –129°

Answer 1

c. 51° ................................

Answer 2

C)
`51^o`

Step-by-step explanation:

As we know that angle in same quadrant with same magnitude is known as coterminal angle

so lets discuss each angle

a)
`591^o`

so we can say it is

`540^o + 51^o`

so it is 51 degree with negative x axis in third quadrant

b)
`231^o`

so we can say it is

`180^o + 51^o`

so it is 51 degree with negative x axis in third quadrant

c)
`51^o`

so it is 51 degree with negative x axis in third quadrant

d)
`-129^o`

so we can say it is

`-180^o + 51^o`

so it is 51 degree with negative x axis in third quadrant

So coterminal angles are 591, 231 , -129