document.write( "Question 1005149: if in ABC triangle ∠C=60∘ then prove that 1/(a+c)+1/(b+c)=3/(a+b+c) \n" ); document.write( "
Algebra.Com's Answer #621513 by richard1234(7193)\"\" \"About 
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Multiply both sides by (a+c)(b+c)(a+b+c) to clear out the fractions and make life easier. That is, statement holds if and only if\r
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\n" ); document.write( "\n" ); document.write( "With some simplification, this is equivalent to\r
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\n" ); document.write( "\n" ); document.write( "However this statement is true by applying the law of cosines on triangle ABC, as angle C = 60 degrees.
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