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Old October 4th, 2007, 08:40 PM
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Determine the angle(s) for the following in the interval from 0-360 degrees. costheta=-0.363.
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Old October 4th, 2007, 10:39 PM
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Originally Posted by rmweeks View Post
Determine the angle(s) for the following in the interval from 0-360 degrees. costheta=-0.363.
If \cos \theta = -0.363

\Rightarrow \theta = \cos^{-1}(-0.363)

\Rightarrow \theta \approx 111.285^{\circ}

this angle is in the second quadrant. another is in the third, using reference angles, we find the other angle to be \approx 248.715

i rounded off a lot, so these answers might not be as accurate as you want them. try to understand what i did and redo the problem with more decimal places if you like
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