document.write( "Question 1017353: 1. In a Triangle ABC, if cotA+cotB+cotC=√3 then prove that the triangle is equilateral triangle. \n" ); document.write( "
Algebra.Com's Answer #633675 by richard1234(7193)\"\" \"About 
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We use the identity that if A, B, C are angles of a triangle, then \r
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\n" ); document.write( "\n" ); document.write( "Dividing both sides by , we obtain\r
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\n" ); document.write( "\n" ); document.write( " (1)\r
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\n" ); document.write( "\n" ); document.write( "The left-hand side equals , so after some rearranging we get:\r
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\n" ); document.write( "\n" ); document.write( "Using the fact that :\r
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\n" ); document.write( "\n" ); document.write( " (2)\r
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\n" ); document.write( "\n" ); document.write( "(2)*2 + (1)*-2 yields the nice expression:\r
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\n" ); document.write( "\n" ); document.write( "which implies that or . Therefore, . \n" ); document.write( "
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