考點:對數(shù)函數(shù)的圖像與性質(zhì),指數(shù)函數(shù)的圖像與性質(zhì),對數(shù)值大小的比較
專題:函數(shù)的性質(zhì)及應(yīng)用
分析:根據(jù)指數(shù)函數(shù)和對數(shù)函數(shù)的圖象和性質(zhì),判斷即可,
解答:
解:對于指數(shù)函數(shù)y=ax和對數(shù)函數(shù)y=logax,當(dāng)a>1時為增函數(shù),0<a<1為減函數(shù),
(1)20.3>2-1.3; (2)0.3-0.5>0.32.1; (3)5-0.6<0.6-5;
(4)log32<log38; (5)log20.3<log0.20.3; (6)log23>log32
(7)log20.2<20.2; (8)5.23-2.1<2.34-2.1; (9)0.23-1>0.27-1
故答案為:(1)>,(2)>,(3)<,(4)<,(5)<,(6)>,(7)<,(8)<,(9)>.
點評:本題主要考查了指數(shù)函數(shù)和對數(shù)函數(shù)的性質(zhì),屬于基礎(chǔ)題.