SOLUTION: If cos £ = -4/9 with £ in Quadrant II, find sin £.

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Question 416378: If cos £ = -4/9 with £ in Quadrant II, find sin £.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If cos £ = -4/9 with £ in Quadrant II, find sin £.
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Note: x is negative in QII.
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cos = x/r = -4/9
Therefore x = -4 and r = 9
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So, y = sqrt[9^2-4^2] = sqrt[65]
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sin = y/r = sqrt(65)/9
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cheers,
Stan H.
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