##  [Law of Sines](/law-sines) 

  ##  [Law of Sines](https://puremath.quantumdictionary.io/law-sines-0) 

  

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- Mathematics & Logic -

**Pure Mathematics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

A relation in any (nondegenerate) Euclidean triangle that equates each side length to twice the circumradius times the sine of its opposite angle, usually expressed as a/sin A = b/sin B = c/sin C (and equal to 2R).