POINT OF INTEREST 4 - THE LAW OF SINES
Copyright by Ingrid Stewart, Ph.D.  Please Send Questions and Comments to ingrid.stewart@csn.edu.

Proof of the Law of Sines

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Let h be the altitude in the triangle above.  Then you have

or

or
Equating these two values of h, you have or .

By constructing an altitude from vertex B to side AC, you can show in a similar manner that