已知x分之一减y分之一等于5,则代数式(2x-11xy-2y)\(x-2xy-y)的值为_数学解答

已知x分之一减y分之一等于5,则代数式
(2x-11xy-2y)\(x-2xy-y)的值为

人气：478 ℃　时间：2019-09-04 02:11:20

解答

1/x-1/y=5
y/(xy)-x/(xy)=5
y-x=5xy
x-y=-5xy
(2x-11xy-2y)/(x-2xy-y)
=[2(x-y)-11xy]/(x-y-2xy)
=[2(-5xy)-11xy]/(-5xy-2xy)
=(-21xy)/(-7xy)
=3