设函数f1(x)=log2x-(12)x,f2(x)=log12x-(12)x的 发布时间:2017-05-04 17:11 │ 来源:www.tikuol.com 题型:选择题 问题: 设函数f1(x)=log2x-(12)x,f2(x)=log12x-(12)x的零点分别为x1,x2,则( )A.0<x1x2<1B.x1x2=1C.1<x1x2<2D.x1x2≥2