SOLUTION: A is a reflexive angle where sin(A)=-5/13. Find cos(4A). Show your step-by-step calculation.

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Question 1107824: A is a reflexive angle where sin(A)=-5/13. Find cos(4A). Show your step-by-step calculation.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A is a reflexive angle where sin(A)=-5/13. Find cos(4A). Show your step-by-step calculation.
Note:: 180 < A < 360
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arcsin(-5/13) = -22.62 degrees = 337.38 degrees
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cos(4A) = cos(4(-22.62)) = cos(-90) = 0
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Cheers,
Stan H.
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