1.函數(shù)f(x)=(2x-1)lnx2零點(diǎn)構(gòu)成的集合為( )
A.{0,-1,1} B.{0,1}
C.{-1,1} D.{1}
2.已知函數(shù)f(x)=-ax在(1,+∞)上有極值,則實(shí)數(shù)a的取值范圍為( )
3.(改編自2020·長(zhǎng)安一中高二月考)給出定義:如果函數(shù)f(x)在[a,b] 上存在x1,x2(a<x1<x2<b),滿足f′(x1)=則稱(chēng)實(shí)數(shù)x1,x2為[a,b] 上的“對(duì)望數(shù)”,函數(shù)f(x)為在[a,b] 上的“對(duì)望函數(shù)”.已知函數(shù)f(x)=-x2+m是[0,m] 上的“對(duì)望函數(shù)”,則實(shí)數(shù)m的可能取值是( )
A.1 B.2
C.3 D.4
4.(改編自2020·成都高三一模)已知函數(shù)f(x)=x+lnx,g(x)=xlnx,若f(x1)=lnt,g(x2)=t,則x1x2lnt的最小值為( )
5.(2020·壽縣一中高三)若α是f(x)=sinx-xcosx在(0,2π)內(nèi)的一個(gè)零點(diǎn),則對(duì)于?x∈(0,2π),下列不等式恒成立的是( )
D.α-cosα≥x-cosx
6.(2020·丹東高三)設(shè)函數(shù)f(x)=xln2x+x的導(dǎo)函數(shù)為f′(x),則( )
B.x=是f(x)的極值點(diǎn)
C.f(x)存在零點(diǎn)
D.f(x)在)單調(diào)遞增
7.函數(shù)f(x)的導(dǎo)函數(shù)為f′(x),若已知f′(x)圖象如圖,則下列說(shuō)法錯(cuò)誤的是( )
(第7題)
A.f(x)存在極大值點(diǎn)
B.f(x)在(0,+∞)單調(diào)遞增
C.f(x)一定有最小值
D.不等式f(x)<0一定有解
8.(改編自2020·濟(jì)南萊蕪一中高三月考)定義方程f(x)=f′(x)的實(shí)數(shù)根x0叫做函數(shù)f(x)的“新駐點(diǎn)”.若函數(shù)g(x)=ln(x+1)的“新駐點(diǎn)”為x0,且x0∈(n,n+1),n∈N,則n的值為_(kāi)_______.
9.已知函數(shù)f(x)=x(aex-e-x)為偶函數(shù),函數(shù)g(x)=f(x)+xe-x,則a=______;若g(x)>mx-e對(duì)x∈(0,+∞)恒成立,則m的取值范圍為_(kāi)_______.
10.(改編自2020·山西高三期中)設(shè)函數(shù)f(x)=xlnx.
(1)設(shè)g(x)=,求g(x)的極值點(diǎn);
(2)證明:當(dāng)x2>x1>0時(shí),>f(x2)-f(x1).
11.已知函數(shù)f(x)=x3-kx+k2.
(1)討論f(x)的單調(diào)性:
(2)若f(x)有三個(gè)零點(diǎn),求k的取值范圍.