求解答初一三道题目.【分式】① 2/(x²-1)+1/(1-x)②化简:(x³-x²)/(x²-x)-(x²-4x+4)/(2-x)③若x²-4x+1=0,求x²+1/x²的值上面三题请附带解题过程.

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求解答初一三道题目.【分式】①2/(x²-1)+1/(1-x)②化简:(x³-x²)/(x²-x)-(x²-4x+4)/(2-x)③若x²-

求解答初一三道题目.【分式】① 2/(x²-1)+1/(1-x)②化简:(x³-x²)/(x²-x)-(x²-4x+4)/(2-x)③若x²-4x+1=0,求x²+1/x²的值上面三题请附带解题过程.
求解答初一三道题目.【分式】
① 2/(x²-1)+1/(1-x)
②化简:(x³-x²)/(x²-x)-(x²-4x+4)/(2-x)
③若x²-4x+1=0,求x²+1/x²的值
上面三题请附带解题过程.

求解答初一三道题目.【分式】① 2/(x²-1)+1/(1-x)②化简:(x³-x²)/(x²-x)-(x²-4x+4)/(2-x)③若x²-4x+1=0,求x²+1/x²的值上面三题请附带解题过程.
① 2/(x²-1)+1/(1-x)
=2/(x²-1)-1/(x-1)
=(2-(x+1))/(x²-1)
=(1-x)/(x²-1)
=-1/(x+1);
②化简:(x³-x²)/(x²-x)-(x²-4x+4)/(2-x)
=x²(x-1)/x(x-1)-(x-2)²/(2-x)
=x-(2-x)
=2x-2;
③若x²-4x+1=0,求x²+1/x²的值
x-4+1/x=0;
x+1/x=4;
x²+1/x²=(x+1/x)²-2=16-2=14;
如果本题有什么不明白可以追问,

2/(x²-1)+1/(1-x)
= 2/(x²-1)-(x+1)/(x²-1)
=-(x-1)/(x²-1)
=-1/(x+1)
(x³-x²)/(x²-x)-(x²-4x+4)/(2-x)
=x²(x-1)/x(x-1)-(x-2)²/(2-x)
=x-(2-x)
=2x-2;