((4x^2-12xy+9y^2)-(4x^2-9y^2))/(2x-3y)
化简:x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y)
(x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)
因式分解:4a^2(x-y)+9(y-x) -4x^2y^2+x^3y+4xy^3
4x^2y+12xy+9y
x^2y+4xy+4y
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
xy=-2,x+y=3,求代数式(4xy+12y)+[7x-(3xy+4y-x)]
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
(x^-4y^)/(x^+2xy+y^)/(x+2y)/(2x^+2xy)
x*-2xy+3y*=9 4x*-5xy+6y*=30
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?