已知y-x=3xy 求2x+5xy-2y/x-2xy-y已知分式x(x-3)/(x^2+1)的值为零,则2x/(x^2-1)÷3x/(1-x)的值为多少,

问题描述:

已知y-x=3xy 求2x+5xy-2y/x-2xy-y
已知分式x(x-3)/(x^2+1)的值为零,则2x/(x^2-1)÷3x/(1-x)的值为多少,