已知a+b+c=0,1/a+1 +1/b+2 +1/c+3=0,求(a+1)^2+(b+2)^2+(c+3)^2

如题所述

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题目没错的话,不是很简单。

如果是,a+b+c=0,1/(a+1)+1/(b+2)+1/(c+3)=0的话,简单:
1/(a+1)+1/(b+2)+1/(c+3)=0 => [(b+2)(c+3)+(a+1)(c+3)+(a+1)(b+2)]/[(a+1)(b+2)(c+3)]=0
=>(b+2)(c+3)+(a+1)(c+3)+(a+1)(b+2)=0
(a+1)^2+(b+2)^2+(c+3)^2
=[(a+1)+(b+2)+(c+3)]^2-2[(a+1)(b+2)+(a+1)(c+3)+(b+2)(c+3)]
=(a+b+c+6)^2
=36
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第1个回答  2011-07-13
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过程??

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