SOLUTION: Given cosA = -1/4 and 90 degrees < A < 180 degrees, find tanA in surd form.

Question 751757: Given cosA = -1/4 and 90 degrees < A < 180 degrees, find tanA in surd form.
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
Given cosA = -1/4 and 90 degrees < A < 180 degrees, find tanA in surd form
sec(A)=1/cos(A)=-4
(in Q2 where tan<0)
..
Check with calculator:
cos(A)=-1/4
A≈104.4775�
tan(A)=tan(104.4775�)≈-3.873..
Exact value=-√15≈-3.873..
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