(xy+1)(x+1)(y+1)+xy怎么因式分解

xy-1+x-y (xy+1)(x+1)(y+1)+xy (xy+1)(x+1)(y+1)+xy (xy+1)(x+1)(y+1)+xy 分解因式(xy+1)(x+y+xy+1)+xy 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 .(x+y-2)(x+y-2xy)+(xy-1)^2 因式分解xy-x-y+1 xy+x+y+1因式分解 1-x-y+xy 因式分解 因式分解:xy+x+y+1 xy-1+x-y因式分解 xy-x-y+1因式分解 钻机XY-1 ,X,Y, 化简xy-1-x+y 计算3xy[2xy-x(y-2)+x-1] xy(xy+1)+xy+3-2(x+y+1/2)-(x+y-1)^2因式分解 因式分解（x+y)(x+y+2xy)+(xy+1)(xy-1)