计算1.(2/9x^2y-4xy^2-5x^2y^2)÷(2/3xy)

计算1.(2/9x^2y-4xy^2-5x^2y^2)÷(2/3xy) 计算：5xy^2-[3xy^2-(4xy^2-2x^2y)]+2x^2y-xy^2 计算:2xy/(x+y)².(x+y)/4y （x^2+xy/x-y)/（xy/x-y)计算 计算：[(x-y)^2-(x+y)^2]/(-4xy)= 计算5x^3y*(-3y)^2+(-6xy)^2*(-xy)-xy^3(-4x)^2 x-y/xy-y^2计算 计算4x^2+9y^2-6xy 计算4x^2+9y^2-6xy 计算(-xy)(x+2x²y) 计算:4xy-(x+y)^2/xy(x+y)(x-y)÷x^2+xy-2y^2/x^2y+2xy^2 计算（xy-y^2)÷x-y/xy 计算：(5-xy/x^3-x^2y)/(1-5/xy)^2*(y-x)^3 计算：（1）8x^2y^2*(-3x/4y^5) (2)(x+y)^2/xy-y^2*(y-x)^2/xy+y^2 计算：3xy[2xy-x（y-2）+x] 计算3xy[2xy-x(y-2)+x-1] 计算(5x^2y^2+4xy^3)÷(8xy) 计算x²y³-2x(4xy³)