x^2-3xy-18y^2-3x-9y
(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)
化简:x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y)
(x+y)(x-y)-(2xy+3y)平方
[x(x^2y^2-xy)-y(x^2-x^3y)]/3x^2y
1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y)
x^2-xy-6y^2+3xy+y+2
数学题(x+y+3)(x^2+y^2+2xy-3x-3y+9)
(3xy)平方/(-xy)+(x-2y)平方-(x+2y)(x-2y)=
9xy(x-y)(x+1)-3y(x-y)(3x+2y)+6y的平方(x-y)(x+1),因式分解
因式分解:4a^2(x-y)+9(y-x) -4x^2y^2+x^3y+4xy^3
计算3xy[2xy-x(y-2)+x-1]
计算:3xy[2xy-x(y-2)+x]