SOLUTION: let theta be an angle in quadrant 4 such that cos theta = 7/8. find exact values of csc theta and cot theta

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Question 484186: let theta be an angle in quadrant 4 such that cos theta = 7/8. find exact values of csc theta and cot theta
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
let theta be an angle in quadrant 4 such that cos theta = 7/8. find exact values of csc theta and cot theta
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Cosine is positive in Q4; only y values are negative in Q4.
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Since cos(theta) = 7/8, x = 7 and r = 8
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Then y = sqrt[8^2-7^2] = sqrt[15]
So y = -sqrt(15)
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csc(theta) = r/y = 8/(-sqrt(15)) = -8/sqrt(15)
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cot(theta) = x/y = 7/(-sqrt(15)) = -7/sqrt(15)
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Cheers,
Stan H.
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