SOLUTION: I have calculated this: cos(-x)= -1/2 cos(x)= 1/2 x=60 degrees + 2 pi Above answer is wrong, but what is wrong? I would be happy if you help me find the right answer and

Question 711661: I have calculated this:
cos(-x)= -1/2
cos(x)= 1/2
x=60 degrees + 2 pi
Above answer is wrong, but what is wrong?
I would be happy if you help me find the right answer and show the calculation step by step so I know how to do it and see what I did wrong.
Thank you for helping me!
Answer by Alan3354(69443) (Show Source): You can put this solution on YOUR website!
I have calculated this:
cos(-x)= -1/2
cos(x)= 1/2 ************ cos(-x) = cos(x)
x = �120 degs � n*360, n = 0,1,2,3...
==============
x=60 degrees + 2 pi Not a good idea to mix degs and radians.
Above answer is wrong, but what is wrong?
I would be happy if you help me find the right answer and show the calculation step by step so I know how to do it and see what I did wrong.
Thank you for helping me!
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