1、(2x-5y) (4x-2y) 2、6a（a-4）-（2a-3）（3a+1） 3、（a-1）（a²+a+1）

化简[(3x+4y)^2-(2x+y)(2x-y)+(-x+y)(5x-y)]除以-2y,其中x=-1,y=1 4x+2y-5x-y 因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² [(-x-y)(-x+y)-(x+y)^2-x(y-y^2)}÷1/2y [(x+y)(x-y)-(x-y)²+2y(x-y)]÷4y [(2x+y)^2-(x+y)(x-4y)-5y^2]除以2x (2x-y)(3x-4y)-2(x-y)(2x-5y)简便运算 把4（x-y+1)+y(y-2x)因式分解 y(y+2)+4x(x-y-1)因式分解是多少 5/4(x+y)(-x-y)^3*[-4/3(x-y)]*[-3/5(y-x)^2] 3(x+y)+2(x-y)=36 4(x+y)-5(x-y)=2 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 4(x-y)-3(x-y)=9 5(x-y)+2(x-y)=11 3(x+y)-4(x-y)=11,2(x-y)+5(x+y)=27 x*x+2x+y*y-4y+5=0 x= y= 5x^3y(x-y)^3-10x^4y^3(y-x)^2因式分解 5x^3y(x-y)^3-10x^4y^3(y-x)^2