x-1/x=1(x>0)则x^4-1/x^4=?答案是3根号5

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x-1/x=1(x>0)则x^4-1/x^4=?答案是3根号5x-1/x=1(x>0)则x^4-1/x^4=?答案是3根号5x-1/x=1(x>0)则x^4-1/x^4=?答案是3根号5(x-1/x)

x-1/x=1(x>0)则x^4-1/x^4=?答案是3根号5
x-1/x=1(x>0)则x^4-1/x^4=?
答案是3根号5

x-1/x=1(x>0)则x^4-1/x^4=?答案是3根号5
(x-1/x)^2=1 => x^2+1/x^2=3
(x^2+1/x^2)^2=9 => x^4+1/x^4=7
(x^4+1/x^4)^2=49 => (x^4-1/x^4)^2=45
因为x>0,且x-1/x>0,故,x^4-1/x^4>0,所以,x^4-1/x^4=3根号5