已知1/x-1/y=2,求5x+3xy-5y/x-2xy-y

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已知1/x-1/y=2,求5x+3xy-5y/x-2xy-y

已知1/x-1/y=2,求5x+3xy-5y/x-2xy-y
已知1/x-1/y=2,求5x+3xy-5y/x-2xy-y

已知1/x-1/y=2,求5x+3xy-5y/x-2xy-y
1/x-1/y=2
(y-x)/xy=2
y-x=2xy
5x+3xy-5y/x-2xy-y
=[5(x-y)+3xy]/[(x-y)-2xy]
=(-10xy+3xy)/(-2xy-2xy)
=7/4

∴1/x-1/y=2
∴y-x=2xy
∴(5x+3xy-5y)/(x-2xy-y)
=[5(x-y)+3xy]/[(x-y)-2xy]
=(-10xy+3xy)/(-2xy-2xy)
=(-7xy)/(-4xy)
=7/4

1/x-1/y=2
y-x=2xy
xy=(y-x)/2
(5x+3xy-5y)/(x-2xy-y)
=[5x+3(y-x)/2-5y)/[x-2(y-x)-y]
=[7(x-y)/2]/2(x-y)
=7/4

哥们我觉得你的请问应该改一改。不然很容易让人造成误会。
(5x+3xy-5y)/(x-2xy-y)