Maths-
General
Easy

Question

In a ABC, 2s = perimeter and R = circum-radius. Then s/R is equal to :

  1. sin A + sin B + sin C  
  2. cos A + cos B + cos C  
  3. sin A/2 + sin B/2 + sin C/2  
  4. none of these  

The correct answer is: sin A + sin B + sin C

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