x^2-xy-2y^2=0是怎么变成（x+y)(x-2y）=0求解,

x^2-xy-2y^2=0是怎么变成（x+y)(x-2y）=0求解, x2+Xy-2Y2=0是如何变成（x-y）（x+2Y) 2x^2-3xy-2y^2=0,怎么变成(2x+y)(x-2y)=0 2x^2-3xy-2y^2=0,怎么变成(2x+y)(x-2y)=0 已知2x-y=10,求式子[(x^2+y^2)-(x-y)^2+2y(x-y)]/4y (4xy-2y²)/4y是怎么变成=2y(2x-y)÷4y x^2+3xy+2y^2/x^2+2xy^2 怎样因式分解?答案是变成(x+2y)(x+y)/xy(x+2y),是怎么化的? x的平方+xy-2y(x+y)x²-xy-2y²怎么变成(x+y)(x-2y) (x^2-xy)y÷y-x/xy怎么做? 已知2x-y=10,求（(x^2+y^2)-(x-y)^2+2y(x-y))/4y-(x-y)'2怎么变成)-(x^2-2xy+y^2) x^-xy-2y^=0怎么化简成(x-2y)(x+y)=0 (X+Y)（X^2+XY+Y^2)+2007(X+Y)=0 这个怎么得到的 暑假作业因式分解(x+y-2xy)(x+y)+(xy-1)2急,最后的2是（xy-1)的平方的意识变成(x+y-2xy)(x+y-2)+(xy-1)2 y＝y(x) e^(xy)－xy＝2 两边对x求导数怎么做?答案是dy/dx=-y/xy=(x)是条件 若1/x-1/y=2,求3x-2xy-3y/x-xy-y的值3x-2xy-3y/x-xy-y 不好意思，是3x-2xy-3y/x-2xy-y (x^3+y^3)(x+y)变成（x+y）^2 *(x^2-xy+y^2)急求(x+y)(x^3+y^3)=(x+y)^2(x^2-xy+y^2) X^2-2XY+Y^2-X+Y-2=0怎么算等于(x-y-2)(x-y+1)? 已知1/x - 1/y = 2,求3x+7xy-3y / 2x-3xy-2y的值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)=-1/71/x-1/y=2到(y-x)/xy=2 是怎么变化的.. 5x+11y-3xy怎么变成2(x-1)+8(y-1)=3(x-1)(y-1)?我的这个问题是有关于高中不等式的。原题是：已知x>1,y>1,且5x+11y-3xy=13,求x+y的最小值．答案的说明是由x>1，y>1，得x-1>0,y-1>0,又由5x+11y-3xy=13 2(x-1)+8(y-1)=3(x-1