SOLUTION: Find cos x/2 when given cot theta= -24/7 and 90 degrees < theta < 180

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Question 1072629: Find cos x/2 when given cot theta= -24/7 and 90 degrees < theta < 180
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Find cos x/2 when given cot theta= -24/7 and 90 degrees < theta < 180
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assuming x and theta are the same:
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cot = x/y = (-24)/7, x negative in Q2
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r = sqrt(x^2+y^2) = 25
cos(x) = y/r = -24/25
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cos^2(x/2) = (1 + cos(x))/2 = 1/50
cos(x/2) = sqrt(1/50) = sqrt(2)/10 (positive in Q1)