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先化简再求值x²-x/(x+1)×x²-1/(x²-2x+1)

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先化简再求值x²-x/(x+1)×x²-1/(x²-2x+1)
先化简再求值:x²-x/(x+1)×x²-1/(x²-2x+1),其中x满足x²-3x+2=0
先化简再求值x²-x/(x+1)×x²-1/(x²-2x+1)
x²-3x+2=(x-1)(x-2)=0
x=1,x=2
x=1,分母x²-2x+1=0,舍去
所以x=2
原式=[x(x-1)/(x+1)][(x+1)(x-1)/(x-1)²]
=x(x-1)(x+1)(x-1)/[(x+1)(x-1)²]
=x
=2