(2x^2y-4xy^2+6y^3)\(-1\2y)(4)[(x+1)(x+2)-2]\x

因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) xy-2{xy-[3x^2y-(4xy^2+0.5xy)]+4x^2y}+6xy^2 5x^3y*(-3y)^2+(-6xy)^2*(-xy)+xy^3*(-4x^2) （X-3xy+4xy-y）-[-2x-2（xy-3/2xy）-y]+6xy的过程 x^2-xy-6y^2+3xy+y+2 诺x+y=6,xy=4 求(5x-4y-3xy)-(8x-y+2xy) x^+2xy+y^+4=16 x^-2xy+y^=16 求(3xy+6y^)+|x^-(2xy+2y^-3x^)|的值 2(x*x-3xy-2y*y+2)- =-4y*y-6xy+3x 化简求值x-4y/2x-7xy+3y×x-2xy-3y/2x+3xy-2y÷3x-6y/4x-4xy+y,其中：x=1999,y=-1 4xy-[(x²+5xy-y²)-(3xy-1/2y)]x=3,y=-6 化简：x-y/x+3y÷x^-y^2/x^2+6xy+9y^2-(xy/x+y) 1、(-7x^y)(2x^y-3xy^3+xy) 2、((x-y)^6)/((y-x)^3)/(x-y) 已知1/x-1/y=2,求3x+7xy-3y/2x-3xy-2y答案是1/x-1/y=2(y-x)/xy=2 得：x-y=-2xy(3x+7xy-3y)/(2x-3xy-2y)=[3(x-y)+7xy]/[2(x-y)-3xy]=(-6xy+7xy)/(-4xy-3xy)=xy/(-7xy)=-1/7 谁能帮我解释一下=[3(x-y)+7xy]/[2(x-y)-3xy]=(-6xy+7xy)/(-4xy-3xy) 是怎 若x+y=4,x-y=6,求xy(y^2+y)-y^2(xy+2x)-3xy的值. 已知；x+y=4,x-y的绝对值=6,求xy(y的平方+y)-y的平方（xy+2x）-3xy先化简再求值 已知x+y=4,x-y=6,化简xy（y²+y）-y²（xy+2x）-3xy 因式分解：x(y-3)-(2y-6) (x+y)^3-(x-y)^2(x+y) x(x^2-xy)-(4x^2-4xy)