计算3y/xy-2x+6/2x-xy 很急很急!求帮助!

计算：3xy[2xy-x（y-2）+x] 计算3xy[2xy-x(y-2)+x-1] 计算：3xy(x²y-xy²+xy)-xy²(2x-xy+2x） （x^2+xy/x-y)/（xy/x-y)计算 计算5x^3y*(-3y)^2+(-6xy)^2*(-xy)-xy^3(-4x)^2 计算：5xy^2-[3xy^2-(4xy^2-2x^2y)]+2x^2y-xy^2 计算3y/xy-2x+6/2x-xy 很急很急!求帮助! (2X平方y+3xy平方)-(6x平方-3XY平方)（计算） 计算(-xy)(x+2x²y) 3xy(x^2y-xy^2+xy)-xy^2(2x^2-6xy+2x)过程 xy-2{xy-[3x^2y-(4xy^2+0.5xy)]+4x^2y}+6xy^2 （X-3xy+4xy-y）-[-2x-2（xy-3/2xy）-y]+6xy的过程 计算（xy-y^2)÷x-y/xy 计算:(x^2-2xy)/(x^2-3xy+2y^2)-(xy+y^2)/(x^2-y^2) 计算：(5-xy/x^3-x^2y)/(1-5/xy)^2*(y-x)^3 x-y/xy-y^2计算 计算:2x^2y(-2xy^2)+(2xy)^3(-xy^2)^2 计算xy^2(-xy)^2-3/2xy^3*4/3x^2y