SOLUTION: Cos120°=-1/2

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Question 1011485: Cos120°=-1/2
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Cos120°=-1/2
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Yes.
Reference angle is 180-120 = 60 Degrees
cos(60) = 1/2
But cos is negative in QII
So cos(120) = -1/2
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Cheers,
Stan H.
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