若3x^2-24x+3=0,則x^2+(1/x^2)=?
原式除以3x => x-8+(1/x)=0 => x+(1/x)=8
[x+(1/x)]^2=64 => x^2+(1/x^2)=62
請問還有別的解法嗎?
謝謝
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