X平方加X平方分之一等于4,求X减X的平方

求X减X分之一等于多少,要有详细讲解

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x^2+1/x^2=4

x^2-2+1/x^2=4-2

x^2-2*x*1/x+1/x^2=2

(x-1/x)^2=2

x-1/和肆芹唤毕x=根号2或-根雹槐号2

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x^2 + 1/x^2 = 4

x^2 - 2 + 1/蔽饥念x^2 = 2

(X - 1/宏困肢拍X)^2=2

X-1/X=±√2

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1/(X^2+X^2)=4 得X=正负根号1/8 带入分别算出来就OK了

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