Sunday, May 26, 2013

if a/b+b/a=1 find a^3+b^3

%0D%0Aa%2Fb%2Bb%2Fa=1%0D%0A 

%0D%0A%28a%2Fb%2Bb%2Fa%29ab=1%2Aab%0D%0A 



%0D%0Aa%5E2%2Bb%5E2=ab%0D%0A 



a%5E2-ab%2Bb%5E2=0 


but 



a%5E3%2Bb%5E3=%28a%2Bb%29%28a%5E2-ab%2Bb%5E2%29=%28a%2Bb%29%2A0 


so 


a%5E3%2Bb%5E3=0 


:)
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