已知x^2-4x+1=0,求（x^2+x^-2)/(x^2+x-2)的值。（要过程） 5
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x²-4x+1=0=>x²=4x-1代入(4x-1)(5x-3)
(x²+x-²)/(x²+x-2)
=(4x-1+1/(4x-1))/(4x-1+x-2)
=(16x²-8x+2)/[(4x-1)(5x-3)]
=(16x²-2(4x-1))/[(4x-1)(5x-3)]
=14x²/x²(5x-3)
=14/(5x-3)
x^2-4x+1=0=>x=2±√3
代入即可
(x²+x-²)/(x²+x-2)
=(4x-1+1/(4x-1))/(4x-1+x-2)
=(16x²-8x+2)/[(4x-1)(5x-3)]
=(16x²-2(4x-1))/[(4x-1)(5x-3)]
=14x²/x²(5x-3)
=14/(5x-3)
x^2-4x+1=0=>x=2±√3
代入即可
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