【答案】
分析:根據(jù)指數(shù)函數(shù)、對數(shù)函數(shù)、冪函數(shù)的單調(diào)性進行驗證即可.
解答:解:∵y=
是單調(diào)遞減函數(shù)且x<y∴
>
排除A
∵y=
在x>0時單調(diào)遞減且0<x<y∴
>
排除B.
y=log
2x單調(diào)遞增且0<x<y∴l(xiāng)og
2x<log
2y∴
∴
故C對.
故選C.
點評:本題主要考查指數(shù)函數(shù)和對數(shù)函數(shù)的單調(diào)性.當?shù)讛?shù)大于1時函數(shù)單調(diào)遞增,當?shù)讛?shù)大于0小于1時函數(shù)單調(diào)遞減.