秀沿路空中泳池:解一道分式题

来源:百度文库 编辑:中科新闻网 时间:2024/05/05 14:15:49
已知1/x-1/y=3
求分式(4x-5xy-4y)/(3x-2xy-3y)的值.

1/x - 1/y =3
(y-x)/xy =3
y-x =3xy
(4x-5xy-4y)/ (3x-2xy-3y)
=(4(x-y)-5xy )/(3(x-y)-2xy)
=(4*-3xy-5xy)/(3*-3xy-2xy)
=-17/(-11)
=17/11