已知X分之1-Y分之1=3则 2x+3xy-2y分之X-2XY-Y的值是.

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已知X分之1-Y分之1=3则 2x+3xy-2y分之X-2XY-Y的值是.
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已知X分之1-Y分之1=3则 2x+3xy-2y分之X-2XY-Y的值是.
已知X分之1-Y分之1=3则 2x+3xy-2y分之X-2XY-Y的值是.

已知X分之1-Y分之1=3则 2x+3xy-2y分之X-2XY-Y的值是.
1/x-1/y=3
(y-x)/(xy)=3
y-x=3xy
(x-2xy-y)/(2x+3xy-2y)=[-(y-x)-2xy]/[-2(y-x)+3xy]=(-3xy-2xy)/(-6xy+3xy)=5/3

1、1/x-1/y=3
得x=y/(3y-1)
2、x-2xy-y=y/(3y-1)-y*2y/(3y-1)-y=y(y+2)/(3y-1)
2x+3xy-2y=2y/(3y-1)+y*3y/(3y-1)-2y=y(4-3y)/(3y-1)
3、(X-2XY-Y)/(2x+3xy-2y)=y(y+2)/(3y-1)/y(4-3y)/(3y-1)=(y+2)/(4-3y)