先化简,再求值:(3x+4/x的平方-1-2/x-1)÷x+2/x的平方-2x+1,其中x是方程8x-5=3x的解

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(3x+4/x的平方-1-2/x-1)÷x+2/x的哗哗平方-2x+1,
=[（3x+4-2(x+1))/(x^2-1)] *(x^2-2x+1)/(x+2)
=[（3x+4-2x-2)/(x-1)(x+1)] * (x-1)^2/(x+2)
=[（x+2)/(x-1)(x+1)] * (x-1)^2/(x+2)
=(x-1)/(x+1)
其中x是方程乱配行8x-5=3x的解
则有x=1
上式=(1-1)/卖枣(1+1)=0

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原式=（3+4/纤模悉(x^3)-2/毁乎(x^2)-2/x）+2/(x^2)-2x+1
=4/(x^3)-2/x-2x+4
=（带入x=1）码宽4-2-2+4
=4

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