SOLUTION: If sin A= 5/13 for angle A in Quadrant I, find cos A/2.

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Question 1098256: If sin A= 5/13 for angle A in Quadrant I, find cos A/2.
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
This is a 5-12-13 triangle
cosine is 12/13
cosine of a/2=sqrt (1 + cos a)/2
=sqrt(25/13/2)=sqrt(25/26)