SOLUTION: sin3A / sinA + cos3A / cosA = 4cos2A Please to do this using as least steps as possible please?\ Thanks!!

SOLUTION: sin3A / sinA + cos3A / cosA = 4cos2A Please to do this using as least steps as possible please?\ Thanks!!

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Question 752182: sin3A / sinA + cos3A / cosA = 4cos2A
Please to do this using as least steps as possible please?\
Thanks!!
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
A=acute angle
sin3A / sinA + cos3A / cosA = 4cos2A
I assume you meant to write given expression as follows:

4cos^2(A)=1
cos^2(A)=1/4
cos(A)=1/2
A=60� or π/3
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