SOLUTION: If cos £ = -4/5 for £ in Quadrant II, find sin £/2.

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Question 453044: If cos £ = -4/5 for £ in Quadrant II, find sin £/2.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
If cos £ = -4/5 for £ in Quadrant II, find sin £/2.
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sin(L/2) = sqrt[(1-cos(L))/2]
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= sqrt[(1+(4/5))/2]
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= sqrt[(9/5)/2]
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= sqrt[0.9]
--
~ 0.9487
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Cheers,
Stan H.