函數(shù)的單調(diào)性檢測(cè)題及參考答案

1、第1頁共4頁函數(shù)的單調(diào)性檢測(cè)題函數(shù)的單調(diào)性檢測(cè)題一、選擇題一、選擇題1若是的單調(diào)增區(qū)間，，且，則有)(ba)(xf??baxx21?21xx?A????21xfxf?B????21xfxf?C????21xfxf?D????021?xfxf2函數(shù)的單調(diào)遞減區(qū)間為??22??xyA????0B??0??C)2[??D]2(??3下列函數(shù)中，在區(qū)間(0，2)上遞增的是Axy1?Bxy??C1??xyD122???xxy4.若函數(shù)在上單調(diào)遞增

2、，則的取值范圍是12)(??xaxf??0??aA??0??B????0C??01?D????15.設(shè)函數(shù)在上是減函數(shù)，則有xay)12(??RA21?aB21?aC21?aD21?a6.函數(shù)在區(qū)間上是減函數(shù)，則實(shí)數(shù)的取值范圍是2)1(2)(2????xaxxf??2??aA3?aB3?aC3??aD3??a二、填空題二、填空題7函數(shù)的單調(diào)遞增區(qū)間是____________.1??xy8函數(shù)在是增函數(shù)，則、、的大小關(guān)系是.)(xf???

3、?0)2(fa?)2(?fb?)23(fc?9函數(shù)的單調(diào)遞增區(qū)間是_______.32)(2????xxxf10若二次函數(shù)在區(qū)間是減函數(shù)，在區(qū)間上是增45)(2???mxxxf]1(???)1(???函數(shù)，則f(1)=________.第3頁共4頁函數(shù)的單調(diào)性檢測(cè)題函數(shù)的單調(diào)性檢測(cè)題參考答案參考答案一、一、題號(hào)123456答案ADDADB二、二、78910????1bca????13??19三、三、11設(shè)，且，則，??021???xx2

4、1xx?012????xxx則.2112)()(xxxxfxfy??????，∴∴.???021???xx021??xx0??y∴在上是增函數(shù).)(xf??0??12函數(shù)在區(qū)間上單調(diào)遞增證明如下：xxy1??)1[??設(shè)，且，則，?????121xx21xx?012????xxx則212112)1()()(xxxxxxfxfy???????，∴，，，??????121xx0121??xx021??xx0??x∴，∴在區(qū)間上的單調(diào)遞增.0