SOLUTION: Express cos 128 degrees as a function of a positive acute angle. Thank you so much.

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Question 1035979: Express cos 128 degrees as a function of a positive acute angle.
Thank you so much.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Express cos 128 degrees as a function of a positive acute angle.
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128 is in QII where the cosine is negative
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128 is 180-128 = 52 degrees above the x-axis
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Reference angle is 52 degrees
cos(128) = -cos(52)
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Cheers,
Stan H.
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