神马品牌网火蓝刀锋2为什么不出了:数学问题
来源：百度文库 编辑：神马品牌网 时间：2024/05/05 01:35:44
如果1\X-1\Y=3,试求(2X-3XY-2Y)\(X-2XY-Y)
1/x-1/y=3
(y-x)/xy=3
xy=(y-x)/3
代入目标式：
[2x-(y-x)-2y]/[x-(2/3)(y-x)-y]
化简：
[3(x-y)]/[(5/3)(x-y)]
=3/(5/3)
=9/5
(y-x)/xy=3
(2X-4XY-2Y+xy)/(X-2XY-Y)=2+xy/(X-2XY-Y)=z
xy/(X-2XY-Y)=z-2 (X-2XY-Y)不等于0,xy不等于0
(X-2XY-Y)/xy=1/(z-2)
-(y-x)/xy-2=1/(z-2)
-3-2=1/(z-2)
z=9/5
1\X-1\Y=3,则(y-x)/xy=3,因为x,y不等于0，因此y-x=3xy(1)
(2X-3XY-2Y)\(X-2XY-Y)=[2(x-y)-3xy]/[(x-y)-2xy]将(1)带入得：
[2(x-y)-(y-x)]/[(x-y)-2/3(y-x)]=3(x-y)/(5/3)(x-y)=9/5
(y-x)/xy=3
(2X-4XY-2Y+xy)/(X-2XY-Y)=2+xy/(X-2XY-Y)=z
xy/(X-2XY-Y)=z-2 (X-2XY-Y)不等于0,xy不等于0
(X-2XY-Y)/xy=1/(z-2)
-(y-x)/xy-2=1/(z-2)
-3-2=1/(z-2)
z=9/5
[(2x-3xy-2y)/xy]/[(x-2xy-y)/xy]
=(2/y-3-2/x) / (1/y-2-1/x)
=(-6-3) /(-3-2)
=9/5
6/5