3x^2-4xy+6xy-3x^2+2y^2

xy-2{xy-[3x^2y-(4xy^2+0.5xy)]+4x^2y}+6xy^2 （X-3xy+4xy-y）-[-2x-2（xy-3/2xy）-y]+6xy的过程 5x^3y*(-3y)^2+(-6xy)^2*(-xy)+xy^3*(-4x^2) 因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 3xy(x^2y-xy^2+xy)-xy^2(2x^2-6xy+2x)过程 （-3x^y+2xy)-( )=4x^+xy 化简：3x^2-[5xy-(x^y-3xy)+4x^2y-8xy] 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 2x²y-3(2xy-xy)-xy 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 (x-2xy)*(-xy+2y*y)-(3x*x-2xy)(x-9xy+6y*y)答案应为-2x-x*x-3x， 因式分解:12xy^2(y-x)+xy^3(x-y)+4x^2y(x-y) x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2 3(x^2y+xy)-4(xy-2x^2y)-(-xy) 当x-y=2xy时,求4x-3xy-4y/xy XY(XY+3)+(XY+4)+4(X+Y+1)-(X+Y+2)