(-2xy^2)^3+8(-x)^3*(-y^2)*(-y^2)^2
(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)
(x+y)(x-y)-(2xy+3y)平方
x^2-xy-6y^2+3xy+y+2
1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y)
化简:x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y)
已知xy/x+y=2,则代数式3x-5y+8y/-x+3xy-y的值
[x(x^2y^2-xy)-y(x^2-x^3y)]/3x^2y
(3xy)平方/(-xy)+(x-2y)平方-(x+2y)(x-2y)=
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)
x^8-x^7y+x^6y^2-x^5y^3+x^4y^4-x^3y^5+x^2y^-xy^7+y^8
x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2
计算3xy[2xy-x(y-2)+x-1]