已知(1/X )-(1/Y)=1,则(2X+3X-2Y)/(X-2XY-Y)=?

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已知(1/X )-(1/Y)=1,则(2X+3X-2Y)/(X-2XY-Y)=?
已知(1/X )-(1/Y)=1,则(2X+3X-2Y)/(X-2XY-Y)=?

已知(1/X )-(1/Y)=1,则(2X+3X-2Y)/(X-2XY-Y)=?
根据观察,你的题抄错了,真正的问题应该为(2x+3xy-2y)/(x-2xy-y)=?
1/x-1/y=1,(y-x)/xy=1,x-y=-xy
(2x+3xy-2y)/(x-2xy-y)
=(-2xy+3xy)/(-xy-2xy)
=xy/(-3xy)
=-1/3

分子写错了
1/x-1/y=(y-x)/xy=1
y-x=xy
x-y=-xy
原式=[2(x-y)+3xy]/[(x-y)-2xy]
=[2(-xy)+3xy]/[(-xy)-2xy]
==xy/(-3xy)
=-1/3