几道约分的题目x的平方-3x+2/x的平方-1x的立方-4x的平方+3x/x的立方+3x的平方-4x要具体一点 写出各个多项式分解之后的最简形式然后写出具体的约分步骤

3x/x的立方+3x

x-2/x+1
x-3/x+4

1.(x^2-3x+2)/(x^2-1)
=(x-1)(x-2)/[(x+1)(x-1)]
=(x-2)/(x+1);
2.(x^3-4x+3x)/(x^3+3x^2-4x)
=x(x^2-4x+3)/[x(x^2+3x-4)]
=(x^2-4x+3)/(x^2+3x-4)
=(x-1)(x-3)/[(x-1)(x+4)]
=(x-3)/(x+4).