约分 2bc/ac 【x+y】y/xy^2 x^2+xy/[x+y]^2 x^2-y^2/[x-y]^2

（x^2+xy/x-y)/（xy/x-y)计算 （xy-x^2)乘以(xy)/(x-y) 因式分解：x×x-xy-2y×y-x-y 把分式xy-y/x-2x+1约分 作乘法:(x+y)(x^2-xy+y^2)；(x-y)(x^2+xy+y^2) 约分：2x²y-2xy²/x²-2xy+y² x^2y+xy^2/xy^3-x^3y约分 x根号x+x根号y/xy-y^2)-（x+根号xy+y/x根号x-y根号）y (x+y-2xy)(x+y-2)+(1-xy)² (x^2-xy)y÷y-x/xy怎么做? (x+y)(x-y)-(2xy+3y)平方 (x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)