计算:2xy/(x+y)².(x+y)/4y

计算：(xy-x²)×x-y/xy （x^2+xy/x-y)/（xy/x-y)计算 x-y/xy-y^2计算 计算：x²+2xy+y²/xy-y².x²-2xy+y²/xy+y&# 计算 2xy[4x²y²-3y（xy+x²y）-xy²] 计算x²y³-2x(4xy³) 计算:4xy-(x+y)^2/xy(x+y)(x-y)÷x^2+xy-2y^2/x^2y+2xy^2 计算3x[xy-2x(1/y-x/3]+3y(x²-y²) 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) 计算：(x+y/x-y)÷(xy+x^2) 分式计算:（x²+2xy+y²）/（x²y+xy）*y/（x+y） 分解因式计算6x³y（x-y)³-4xy³(y-x)²