3x^2+5xy-2y^2+x+9y-4怎么化简

因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 化简：3x^2-[5xy-(x^y-3xy)+4x^2y-8xy] 因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) 3x*x+5xy-2y*y+x+9y-4 3x*x+5xy-2y*y+x+9y-4请因式分解 x²-y²+5x+3y+4（x+y-2xy)(x+y-z)+(xy-1）² x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2 5x^3y*(-3y)^2+(-6xy)^2*(-xy)+xy^3*(-4x^2) 化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) 已知x-y=3xy,求5x+2xy-5y/x-4xy-y的值 诺x+y=6,xy=4 求(5x-4y-3xy)-(8x-y+2xy) 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-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)答案应为-2x-x*x-3x， (-2xy+2x+5y)-(3xy+2y-2x)-(x+4y+xy)其中x-y=4xy=-1 若x-y=4,xy=1,则(2x+y-2xy)-(3x+2y+xy)-(4xy+3y-5x)= 求（3x^+y^-5xy）-【2x^-（-4xy-y^+7x^）】=? 求（3x^+y^-5xy）-【2x^-（-4xy-y^+7x^）】=? 已知x^2+9y^2-2x-6y+2=0,求{-（xy/（x-y）^2}^4*(y^2-xy/x)^3*x^4/y^10/(x/xy-y^2)^5的值