SOLUTION: If cosine theta equals -5/9 and sine theta > 0, find the exact value of tan theta.

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Question 900610: If cosine theta equals -5/9 and sine theta > 0, find the exact value of tan theta.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If cosine theta equals -5/9 and sine theta > 0, find the exact value of tan theta.
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Note:: If cos is negative and sin is positive, theta is in QII
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By definition:: cos = x/r
Since cos = -5/9, x = -5 and r = 9
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Then y = sqrt[9^2-5^2] = sqrt(56) = 2sqrt(14)
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Ans: tan(t) = y/x = -sqrt(56)/5
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Cheers,
Stan H.
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