(x^2+1)x=10670

(x^2+1)x=10670
x^3+x-10670=0
(x-22)(x^2+22x+485)=0
Since x^2+22x+485>0
x=22

2010-04-29 18:10:38 補充：
From x^2+22x+485=0,
Discriminant=22^2-4(485)(1)=-1456<0
x^2+22x+485>0

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