SOLUTION: if tan&#952; = 4 and 180° < &#952; < 270° determine the exact value of cos&#952;

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Question 952106: if tanθ = 4 and 180° < θ < 270° determine the exact value of cosθ
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
if tanθ = 4 and 180° < θ < 270° determine the exact value of cosθ
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tan = y/x = 4/1
r+=+sqrt%28x%5E2+%2B+y%5E2%29+=+sqrt%2817%29
|cos| = x/r = sqrt%2817%29%2F17
cosine is negative in Q3
--> -sqrt%2817%29%2F17