# If for a triangle Cos A + Cos B + Cos C = 3/2, then what is special about the triangle?

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If for a triangle Cos A + Cos B + Cos C = 3/2, then what is special about the triangle?
posted Feb 1, 2015

All angles are 60 degree
Cos60 = 1/2
= 1/2 + 1/2 + 1/2
= 3/2
So triangle is an equilateral triangle

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