Question

設(shè)a，b，c分別是函數(shù)f(x)＝()^x－log₂x，g(x)＝2^x－logx，h(x)＝()^x－logx的零點，則a，b，c的大小關(guān)系是                                                        (　　)

A．b<c<a                           B．a<b<c

C．b<a<c                           D．c<b<a

Answer 1

A

解析　在同一坐標(biāo)系中作出函數(shù)y＝()^x、y＝2^x、y＝logx、y＝log₂x的圖像(如圖)，則有x_A>1>x_C>x_B，即b<c<1<a，故選A.