SOLUTION: given sin(x)=5/13 and x is in quadrant II what is cos(x)?

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Question 791443: given sin(x)=5/13 and x is in quadrant II what is cos(x)?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
given sin(x)=5/13 and x is in quadrant II what is cos(x)?
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Note: In QII x is negative.
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If sin(x) = y/r = 5/13, y = 5 and r = 13
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Then x = sqrt[13^2-5^2] = sqrt[169-25] = 12
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But x is negative in QII.
So cos(x) = x/r = -12/13
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Cheers,
Stan H.