[(xy-1-x+y)÷(y-1)+(y-1)]×2求化简
[(xy-1-x+y)÷(y-1)+(y-1)]×2求化简
(1)x-y/x-2y÷x^2-y^2/x^2-4xy+4y^2
计算(3x^3y-x^2y+1/2xy)÷(-1/2xy)
分解因式:(X+Y)*(X+Y+2XY)+(XY+1)*(XY-1)
xy(xy+1)+(xy+3)-2(x+y+2分之一)-(x+y-1)的平方
先化简再求值(x-y/1-x+y/1)÷x平方+2xy+y平方/2y,其中x=根号3+2,y=根号3
(1)正数x,y满足x^2-y^2=2xy,求(x-y)/(x+y)
y(y+1)(x的平方+1)+x(2xy的平方+2y+1)
(1)3xy×(-4xy+2xy-1)(2)(x+2y)(3x-2y)+(x-2y)(3x+2y)
化简!1、(x^2-xy)+xy+y^2 2、3(x^2-xy)-xy+y^2
1/x-1/y=5求(-x+xy+y)/(2x+7xy-2y)
分解因式:(X+Y-2XY)*(X+Y-2)+(1-XY)∧2