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已知1X1Y=3则代数式(2X已知1/X-1/Y=3则代数式(2

2009-02-19 20:05:25毛***
已知1/X-1/Y=3则代数式(2X-14XY-2Y)/(X-2XY-Y)的值为已知1/X-1/Y=3则代数式(2X-14XY-2Y)/(X-2XY-Y)的值为[过程]已知1X1Y=3则代数式(2X已知1/X-1/Y=3则代数式(2X-14XY-2Y)/(X-2XY-Y)的值为已知1/X-1/Y=3则代数式(2X-14XY-2?

最佳回答

  • 已知1/X-1/Y=3则代数式(2X-14XY-2Y)/(X-2XY-Y)的值为 已知:1/x-1/y=3 所以:1/x-1/y=(y-x)/(xy)=3 即:y-x=3xy 代入到代数式中,就有: (2x-14xy-2y)/(x-2xy-y)=[2(x-y)-14xy]/[(x-y)-2xy] =(-6xy-14xy)/(-3xy-2xy) =(-20xy)/(-5xy) =4
    2009-02-19 20:18:05
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