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Subject: Trigonometry in a triangle
Date: Sat, 25 Jan 1997 18:01:47 -0800
From: Calvin Lui

Hello !I am Ronald who born in Hong Kong. Could you please help me to solve a mathematics question. The question is as following: In triangle ABC, prove :

(b^2-c^2)cotA +(c^2 - a^2)cotB+(a^2-b^2)cotC = 0

some useful formular is : cosine rule & sine rule Thank you very much!!!

 

 

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