已知实数x满足x2-3x+1=0,则代数式x2+1/x2得值为——?

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已知实数x满足x2-3x+1=0,则代数式x2+1/x2得值为——?

已知实数x满足x2-3x+1=0,则代数式x2+1/x2得值为——?
已知实数x满足x2-3x+1=0,则代数式x2+1/x2得值为——?

已知实数x满足x2-3x+1=0,则代数式x2+1/x2得值为——?
x2+1=3x
x2+1/x2
=3x-1+1/(3x-1)
=(9x^2-6x+2)/(3x-1)
=(27x-9-6x+2)/(3x-1)
=(21x-7)/(3x-1)
=7