湖南省岳阳县第一中学2015届高三10月月考数学(文)(附答案)
2015高考真题:文科数学(湖南卷)试卷(含答案)

一、选择题:本大题共10小题,每小题5分,共50分,在每小题给出的四个选项中,只有一项是符合题目要求的.1、已知2(1)iz-=1+i(i为虚数单位),则复数z=( )A、1+iB、1-iC、-1+iD、-1-i 【答案】D【解析】试题分析:.由题根据所给复数式子进行化简即可得到复数z的代数式;由题22(1)(1)22(1i)1,1112i i i ii z iz i i-----=+∴====--++,故选D.考点:复数的运算2、在一次马拉松比赛中,35名运动员的成绩(单位:分钟)如图I所示;若将运动员按成绩由好到差编为1~35号,再用系统抽样方法从中抽取7人,则其中成绩在区间[139,151]上的运动员人数为( )A、3B、4C、5D、6【答案】B考点:茎叶图3、设x∈R,则“x>1”是“2x>1”的()A、充分不必要条件B、必要不充分条件C、充要条件D、既不充分也不必要条件【答案】C【解析】试题分析:.由题根据明天的关系进行发现即可得到所给两个明天的关系;由题易知“x>1”可以推得“2x>1”,“2x>1”可以得到“x>1”,所以“x>1”是“2x>1”的充要条件,故选C.考点:命题与条件4、若变量x、y满足约束条件111x yy xx+≥⎧⎪-≤⎨⎪≤⎩,则z=2x-y的最小值为( )A、-1B、0C、1D、2 【答案】A考点:简单的线性规划5、执行如图2所示的程序框图,如果输入n=3,中输入的S=( )A、67B、37C、89D、49【答案】B考点:程序框图6、若双曲线22221x ya b-=的一条渐近线经过点(3,-4),则此双曲线的离心率为A B、54C、43D、53【答案】D【解析】试题分析:由题利用双曲线的渐近线方程经过的点,得到a、b关系式,然后求出双曲线的离心率即可.因为双曲线22221x ya b-=的一条渐近线经过点(3,-4),2225349163c b a c a a e a ∴=∴-=∴=,(),=. 故选D.考点:双曲线的简单性质7、若实数a ,b 满足12a b+=,则ab 的最小值为( )A B 、2 C 、 D 、4 【答案】C考点:基本不等式8、设函数f (x )=ln (1+x )-ln (1-x ),则f (x )是( )A 、奇函数,且在(0,1)上是增函数B 、奇函数,且在(0,1)上是减函数C 、偶函数,且在(0,1)上是增函数D 、偶函数,且在(0,1)上是减函数 【答案】A 【解析】试题分析:求出函数的定义域,判断函数的奇偶性,以及函数的单调性推出结果即可. 函数f (x )=ln (1+x )-ln (1-x ),函数的定义域为(-1,1),函数f (-x )=ln (1-x )-ln (1+x )=-[ln (1+x )-ln (1-x )]=-f (x ),所以函数是奇函数.()2111'111f x x x x =+=+-- ,已知在(0,1)上()'0f x > ,所以f(x)在(0,1)上单调递增,故选A.考点:利用导数研究函数的性质9、已知点A,B,C 在圆221x y +=上运动,且AB ⊥BC ,若点P 的坐标为(2,0),则PA PB PC ++ 的最大值为A 、6B 、7C 、8D 、9 【答案】B【解析】试题分析:由题根据所给条件不难得到该圆221x y +=是一AC 位直径的圆,然后根据所给条件结合向量的几何关系不难得到24PA PB PC PO PB PB ++++==,易知当B 为(-1,0)时取得最大值.由题意,AC 为直径,所以24PA PB PC PO PB PB ++++== ,已知B 为(-1,0)时,4PB +取得最大值7,故选B.考点:直线与圆的位置关系、平面向量的运算性质10、某工作的三视图如图3所示,现将该工作通过切削,加工成一个体积尽可能大的正方体新工件,并使新工件的一个面落在原工作的一个面内,则原工件材料的利用率为(材料利用率=新工件的体积/原工件的体积)A 、89πB 、827πC 、21)πD 、21)π【答案】A考点:三视图、基本不等式求最值、圆锥的内接长方体 二、填空题:本大题共5小题,每小题5分,共25分. 11、已知集合U={}1,2,3,4,A={}1,3,B={}1,3,4,则A (U B ð)=_____.【答案】{1,2,3}.考点:集合的运算12、在直角坐标系xOy 中,以坐标原点为极点,x 轴正半轴为极轴建立极坐标系.若曲线C 的极坐标方程为2sin ρθ=,则曲线C 的直角坐标方程为_____.【答案】2211x y +-=() 【解析】试题分析:将极坐标化为直角坐标,求解即可.曲线C 的极坐标方程为222sn sn ρθρρθ=∴=,,它的直角坐标方程为222x y y += , 2211x y ∴+-=(). 故答案为:2211x y +-=(). 考点:圆的极坐标方程13. 若直线3x-4y+5=0与圆()2220x y r r +=>相交于A,B 两点,且120o AOB ∠=(O 为坐标原点),则r=_____. 【答案】 【解析】试题分析:直线3x-4y+5=0与圆2220x y r r +=(>)交于A 、B 两点,∠AOB=120°,则△AOB 为顶角为120°的等腰三角形,顶点(圆心)到直线3x-4y+5=0的距离为12r ,代入点到直线距离公式,可构造关于r 的方程,解方程可得答案.如图直线3x-4y+5=0与圆2220x y r r +=(>) 交于A 、B 两点,O 为坐标原点,且∠AOB=120°,则圆心(0,0)到直线3x-4y+5=0的距离为12r 12r r =∴,=2 .故答案为2.考点:直线与圆的位置关系14、若函数f (x )=| 2x-2 |-b 有两个零点,则实数b 的取值范围是_____. 【答案】0<b <2考点:函数零点15、已知ω>0,在函数y=2sin ωx 与y=2cos ωx 的图像的交点中,距离最短的两个交点的距离为,则ω =_____. 【答案】2πω=考点:三角函数图像与性质三、解答题:本大题共6小题,共75分,解答应写出文字说明,证明过程或演算步骤。
2024-2025学年湖南省岳阳市岳阳县一中高三(上)月考数学试卷(10月份)(含答案)

2024-2025学年湖南省岳阳市岳阳县一中高三(上)月考数学试卷(10月份)一、单选题:本题共8小题,每小题5分,共40分。
在每小题给出的选项中,只有一项是符合题目要求的。
1.已知集合A ={x|x >1},B ={x|x 2+3x−4≥0},则( )A. A ∩B =⌀ B. A ∪B =RC. A ⊆BD. B ⊆A2.已知复数z =2+i 20231+i,则z 的共轭复数−z 在复平面中对应的点在第( )象限A. 一B. 二C. 三D. 四3.关于三个不同平面α,β,γ与直线l ,下列命题中的假命题是( )A. 若α⊥β,则α内一定存在直线平行于βB. 若α与β不垂直,则α内一定不存在直线垂直于βC. 若α⊥γ,β⊥γ,α∩β=l ,则l ⊥γD. 若α⊥β,则α内所有直线垂直于β4.已知奇函数f(x)在R 上可导,g(x)=f′(x),若g(x)在(0,1)是增函数,在(1,+∞)是减函数,则( )A. g(x)在(−∞,−1)是增函数,在(−1,0)是减函数 B. g(x)在(−∞,−1)是减函数,在(−1,0)是增函数C. g(x)在(−∞,−1),(−1,0)都是增函数 D. g(x)在(−∞,−1),(−1,0)都是减函数5.如图,在平面直角坐标系xOy 中,已知点A(−3,4),∠BOx =π4,记∠AOB =θ,则cos (θ−π4)=( )A. −35 B. 35 C. −45 D. 456.如今我们在测量视力的时候,常用对数视力表(如图),视力值从4.0到5.3,每行相差0.1,这种计算视力的方法称为五分记录法,“对数视力表”和“五分记录法”是由我国著名眼科专家缪天荣(1914−2005)在1959年研制发明的,这种独创的视力表的核心在于:将视力和视角设定为对数关系,因此被认为是一种最符合视力生理的,而又便于统计和计算的视力检测系统,这使中国的眼科研究一下子站到了世界的巅峰,1986年,《对数视力表》在第25届国际眼科大会(罗马)宣读,引起轰动,1990年《标准对数视力表》被制定为国家标准(GB11533−89),并在全国实施.已知在五分记录法中,规定视力值L=5−lgα,其中α为人眼的视角,单位为分(1度=60分),视角的大小,决定了人眼能看到的最小物体的长度,这个长度约等于以眼球为圆心(眼球大小忽略不计),视角为圆心角,眼球与物体之间的距离为半径的扇形的弧长.如果某人的一只眼睛的视力值为4.7,那么这只眼睛能看到距离5米外的最小物体的长度约为(参考数据:100.3≈2,π≈3.14)( )A. 1.5毫米B. 2.9毫米C. 4.4毫米D. 5.8毫米7.已知点P是抛物线y2=2x上的动点,点P在y轴上的射影是M,点A(72,4),则|PA|+|PM|的最小值是( )A. 5B. 92C. 4 D. 328.已知过点(a,b)可以作函数f(x)=x3−x的三条切线,如果a>0,则a和b应该满足的关系是( )A. 0<b<a3B. −239<b<a3−aC. −a<b<a3D. −a<b<a3−a二、多选题:本题共4小题,共20分。
湖南省岳阳县一中2015届高三10月第二次月考数学(文)

湖南省岳阳县一中2015届高三10月第二次月考数学(文)一、选择题(下列各小题的四个答案中仅有一个是正确的,请将正确答案填入答题纸的表格中,每小题5分,50分)1.已知全集{}0,1,2,3,4U =,集合{}{}1,2,3,2,4A B ==,则()U A B ð为 ( )A.{}1,2,4B.{}2,3,4C. {}0,2,3,4D. {}0,2,4 2. 函数()sin(2)3f x x π=+的一个对称中心是 ( )A.(,0)3πB. (,0)12πC. (,0)6πD. (,0)12π- 3.将函数y =sin x 的图象上所有的点向右平行移动π10个单位长度,再把所得各点的横坐标伸长到原来的2倍(纵坐标不变),所得图象的函数解析式是 ( )A .y =sin(2x -π10)B .y =sin(2x -π5)C .y =sin(12x -π10)D .y =sin(12x -π20)4.设函数f (x )=⎩⎪⎨⎪⎧⎝⎛⎭⎫12x -7,x <0,x ,x ≥0,若f (a )<1,则实数a 的取值范围是 ( )A .(-∞,-3)B .(1,+∞)C .(-3,1)D .(-∞,-3)∪(1,+∞)5.函数()log 1(01)a f x x a =+<<的图像大致为 ( )6.以下有关命题的说法错误的是( ) A.命题“若2320x x -+=则x =1”的逆否命题为“若21,320x x x ≠-+≠则”B .“1x =”是“2320x x -+=”的充分不必要条件A. B. C.D.C .若p q ∧为假命题,则p 、q 均为假命题D .对于命题22:10,:,10p x R x x p x R x x ∃∈++<⌝∀∈++≥使得则均有7. 已知一元二次函数2()f x x bx c =++,且不等式20x bx c ++>的解集为{}1|<-1>2x x x 或,则(10)>0x f 的解集为 ( ) A .{}|<-1>lg2x x x 或 B .{}|-1<<lg2x x C .{}|>-lg2x x D .{}|<-lg2x x8.若函数f (x )=2x 2-ln x 在其定义域内的一个子区间(k -1,k +1)内至少有一个极值点,则实数k 的取值范围是 ( )A .[1,+∞)B .[1,32)C .[1,2) [32,2)9.锐角ABC ∆中,,,a b c 分别是三内角,,A B C 的对边,且2B A =,则ba的取值范围是( )A .(2,2)-B .(0,2)C .2)D .10.定义在(0,)+∞上的函数()f x 满足条件(2)2()f x f x =,且当(1,2]x ∈时,()2f x x =-,若12,x x 是方程() (01)f x a a =<≤的两个实根,则12x x -不可能是( )A .30B .56C .80D .112二.填空题:(共35分把答案填在答题纸相应题号后的横线上) 11.函数ln (0)y x x =>的单调增区间为________________.12.已知函数()ln(1)f x x =++的定义域为M ,则M=13.命题p:x R ∃∈,使2(1)10x a x +++<,若p ⌝为假命题,则实数a 的取值范围是14.函数sin()(0,0,||)2y A x A πωϕωϕ=+>><的部分图象如图所示,则函数的解析式为15.对于三次函数d cx bx ax x f +++=23)()0(≠a ,给出定义:)(x f /是函数)(x f 的导函数,)(//x f 是)(x f /的导函数,若方程0)(//=x f 有实数解0x ,则称点))(,(00x f x 为函数)(x f y =的“拐点”。
湖南省岳阳市岳阳县一中高三数学上学期第二次(10月)月考试卷 理(含解析)

湖南省岳阳市岳阳县一中2015届高三上学期10月月考数学试卷(理科)一、选择题:本大题共10小题,每小题5分,共50分.在每小题给出的四个选项中,只有一项是符合题目要求的,请将所选答案填在答题卡中对应位置.1.设集合P={1,2,3,4,5,6},Q={x∈R|2≤x≤6},那么下列结论正确的是( ) A.P∩Q=P B.P∩Q⊋Q C.P∪Q=Q D.P∩Q⊊P考点:交集及其运算;并集及其运算.专题:计算题.分析:本题考查的集合的运算,我们可以根据已知条件,将四个答案逐一代入运算,进行判断后不难得到答案.解答:解:P∩Q={2,3,4,5,6},∴P∩Q⊊P≠P故A、B错误,故D正确.故选D点评:集合运算时要注意,性质描述法表示的集合,元素取值的范围,本题易忽略Q集合中x∈R,而错认为x∈Z,得到Q═{2,3,4,5,6},而得到错误的结论.2.设p:x∈R,q:2<x<3,则p是q成立的( )A.充分不必要条件B.必要不充分条件C.充分必要条件D.既不充分也不必要条件考点:必要条件、充分条件与充要条件的判断.专题:简易逻辑.分析:由q⇒p,反之不成立.即可判断出.解答:解:由q⇒p,反之不成立.∴p是q成立的必要不充分条件.故选:B.点评:本题查克拉充要条件的判定,属于基础题.3.命题“对任意x∈R,都有x3>x2”的否定是( )A.存在x0∈R,使得x03>x02B.不存在x0∈R,使得x03>x02C.存在x0∈R,使得x03≤x02D.对任意x∈R,都有x3≤x2考点:命题的否定.专题:简易逻辑.分析:利用全称命题的否定是特称命题,特称命题的否定是全称命题,写出结果即可.解答:解:全称命题的否定是特称命题,特称命题的否定是全称命题,∴命题“对任意x∈R,都有x3>x2”的否定是:存在x0∈R,使得x03≤x02.故选:C.点评:本题考查命题的否定,注意否定形式以及量词的变化,基本知识的考查.4.已知扇形的面积为,半径为1,则该扇形的圆心角的弧度数是( ) A.B.C.D.考点:扇形面积公式.专题:计算题;三角函数的求值.分析:半径为r的扇形圆心角的弧度数为α,则它的面积为S=αr2,由此结合题中数据,建立关于圆心角的弧度数α的方程,解之即得该扇形的圆心角的弧度数.解答:解:设扇形圆心角的弧度数为α,则扇形面积为S=αr2=α=,解之,得α=故选:C.点评:本题在已知扇形的面积和半径的情况下,求该扇形圆心角的弧度数.着重考查了弧度制的定义和扇形面积公式等知识,属于基础题.5.已知,则sinx=( )A.B.C.D.考点:诱导公式的作用.分析:由sin2α+cos2α=1及诱导公式可解之.解答:解:∵,∴,即;又x∈(π,2π),∴;故选B.点评:本题考查诱导公式及同角正余弦关系.6.函数y=的定义域为( )A.{x|x≤﹣,或x≥1}B.{x|x<﹣,或x>1} C.{x|x≤0,或x≥} D.{x|x<0,或x>}考点:函数的定义域及其求法.专题:函数的性质及应用.分析:由对数函数的性质及二次根式的性质得2x2﹣x≥1,解出即可.解答:解:∵≥0,∴2x2﹣x≥1,解得:x≤﹣或x≥1,故选:A.点评:本题考查了对数函数的性质及二次根式的性质,求函数的定义域,是一道基础题.7.若定义在R上的函数f(x)满足f(x)=,则f=( ) A.2 B.1 C.0 D.﹣1考点:函数的值.专题:函数的性质及应用.分析:根据解析式先求出当x>0时,函数f(x)的周期为5,再用周期性和解析式得f=f(﹣1),代入解析式求解.解答:解:由题意得,f(x)=,当x>0时,有f(x)=f(x﹣5),则f(x+5)=f(x),所以当x>0时,函数f(x)的周期为5,则f=f(402×5+4)=f(4)=f(4﹣5)=f(﹣1)==1,故选:B.点评:本题考查分段函数的函数的值,以及利用函数的周期求出函数值,属于基础题.8.若函数f(x)=Asin2ωx(A>0,ω>0)在x=1处取得最大值,则f(x+1)的奇偶性为( ) A.偶函数B.奇函数C.既是奇函数又是偶函数D.非奇非偶函数考点:函数奇偶性的判断;正弦函数的图象.专题:函数的性质及应用.分析:根据函数f(x)=Asin2ωx(A>0,ω>0)在x=1处取得最大值,求得ω的值,然后再判断f(x+1)的奇偶性.解答:解:因为函数f(x)=Asin2ωx(A>0,ω>0)在x=1处取得最大值,所以2ω=+2kπ,所以ω=,所以f(x+1)=Asin(+2kπ)(x+1)=Acos(+2kπ)x,所以f(﹣x+1)=Asin(+2kπ)(﹣x+1)=Acos(+2kπ)(﹣x)=Acos(+2kπ)x,所以f(x+1)是偶函数.故选A.点评:本题主要考查函数的奇偶性、正弦函数的最值,属于基础题.9.函数f(x)=sin(x)﹣log2x的零点个数为( )A.1 B.2 C.3 D.4考点:函数的零点.专题:函数的性质及应用.分析:函数f(x)=sin(x)﹣log2x的零点个数,即函数y═sin()与函数 y=log2x 的交点的个数,数形结合求得结果.解答:解:函数f(x)=sin(x)﹣log2x的零点个数,即函数y=sin()的图象与函数y=log2x的图象交点的个数.如图所示:由于函数y=sin()的图象与函数y=log2x的图象的交点的个数为3,故选:C.点评:本题主要考查函数的零点与方程的根的关系,体现了化归与转化、数形结合的数学思想,属于基础题.10.已知两条直线l1:y=m和l2:y=(m>0,m≠),l1与函数y=|log2x|的图象从左至右相交于点A、B,l2与函数y=|log2x|的图象从左至右相交于点C、D.记线段AC和BD在x轴上的投影长度分别为a,b,当m变化时,的最小值为( )A.16 B.8 C.4 D.2考点:对数函数的图像与性质.专题:函数的性质及应用.分析:由题意设A,B,C,D各点的横坐标分别为x A,x B,x C,x D,依题意可求得为x A,x B,x C,x D的值,a=|x A﹣x C|,b=|x B﹣x D|,下面利用基本不等式可求最小值解答:解:设A,B,C,D各点的横坐标分别为x A,x B,x C,x D,则﹣log2x A=m,log2x B=m;﹣log2x C=,log2x D=;∴x A=2﹣m,x B=2m,x C=,x D=.∴a=|x A﹣x C|,b=|x B﹣x D|,∴==又m>0,∴m+=m+1+﹣1≥2﹣1=4﹣1=3,当且仅当m=1时取“=”号,∴≥23=8,故选:B.点评:本题考查对数函数图象与性质的综合应用,理解投影的概念并能把问题转化为基本不等式求最值是解决问题的关键,属中档题.二、填空题:本大题共5小题,共25分,把答案填在答题卡中对应题号后的横线上.11.函数y=3sin(2x+)的最小正周期为π.考点:三角函数的周期性及其求法.专题:三角函数的图像与性质.分析:将题中的函数表达式与函数y=Asin(ωx+φ)进行对照,可得ω=2,由此结合三角函数的周期公式加以计算,即可得到函数的最小正周期.解答:解:∵函数表达式为y=3sin(2x+),∴ω=2,可得最小正周期T=||=||=π故答案为:π点评:本题给出三角函数表达式,求函数的最小正周期,着重考查了函数y=Asin(ωx+φ)的周期公式的知识,属于基础题.12.计算dx的结果是π.考点:定积分.专题:导数的概念及应用.分析:根据定积分的几何意义,∫02dx表示以原点为圆心,以2为半径的圆的面积的四分之一,问题得以解决.解答:解:∫02dx表示的几何意义是以原点为圆心,以2为半径的圆的面积的四分之一,∴∫02dx==π故答案为:π点评:本题主要考查了定积分的几何意义,属于基础题.13.已知sinacosα=且α∈(0,),则cosα﹣sinα=.考点:二倍角的正弦.专题:三角函数的求值.分析:由α∈(0,),可得cosα>sinα.可得cosα﹣sinα==,即可得出.解答:解:∵α∈(0,),∴cosα>sinα.∴cosα﹣sinα===.故答案为:.点评:本题考查了三角函数的单调性、同角三角函数基本关系式,考查了推理能力,属于基础题.14.已知函数f(x)=﹣x2+2mx+1,若∃x0∈R,使得∀x1∈都有f(x1)<f(x0),则实数m的取值范围是(﹣∞,1)∪(2,+∞).考点:二次函数的性质.专题:函数的性质及应用.分析:函数f(x)=﹣x2+2mx+1开口向下、对称轴方程为x=m的抛物线,由∃x0∈R,使得∀x1∈都有f(x1)<f(x0),知m<1或m>2.解答:解:函数f(x)=﹣x2+2mx+1开口向下、对称轴方程为x=m的抛物线,∵∃x0∈R,使得∀x1∈都有f(x1)<f(x0),结合抛物线的形状:如图示:∴m<1或m>2,故答案为:(﹣∞,1)∪(2,+∞).点评:本题考查二次函数的性质,是基础题.解题时要认真审题,仔细解答,注意合理地进行等价转化.15.如图展示了一个由区间(0,1)到实数集R的映射过程:区间(0,1)中的实数m对应数轴上的点M,如图1;将线段AB围成一个圆,使两端点A,B恰好重合(点M从点A按逆时针方向运动至点B),如图2;再将这个圆放在平面直角坐标系中,使其圆心在y轴上,点A的坐标为(0,1),如图3.图3中直线AM与x轴交于点N(n,0),则m的象就是n,记作f (m)=n.下列说法中正确命题的序号是②③⑤.(填出所有正确命题的序号)①f()=1;②f(x)在定义域上单调递增;③方程f(x)=0的解是x=;④f(x)是奇函数;⑤f(x)的图象关于点(,0)对称.考点:进行简单的合情推理.专题:阅读型;函数的性质及应用;推理和证明.分析:由题中对映射运算描述,对五个命题逐一判断其真伪,①m=此时M恰好处在左半圆弧的中点上,求出直线AM的方程后易得N的横坐标,即可判断;②可由图3,由M的运动规律观察出函数值的变化,得出单调性,即可判断;③可由②的单调性,结合图3即可判断;④可由奇偶函数的定义域关于原点对称来确定正误;④可由图3中圆关于y轴的对称判断出正误.解答:解:对于①,因为当m=,此时M恰好处在左半圆弧的中点上,此时直线AM的方程为y=x+1,即f()=﹣1,故①错;对于②,当x从0→1变化时,点N从左边向右边移动,其对应的坐标值渐渐增大,故f(x)在定义域上单调递增,故②正确.对于③,由②f(x)在定义域上单调递增,则M运动到AB的中点,即有直线AM为x=0,即有f()=0,故③正确;对于④,由于函数f(x)的定义域为(0,1),不关于原点对称,则函数f(x)是非奇非偶函数,故④错.对于⑤,由图3可以看出,当M点的位置离中间位置相等时,N点关于y轴对称,即此时函数值互为相反数,故可知f(x)的图象关于点(,0)对称,故⑤正确.故答案为:②③⑤.点评:本题考查映射的概念,解答本题关键是理解题设中所给的对应关系,正确认识三个图象的意义,由此对五个命题的正误作出判断,本题题型新颖,寓数于形,是一个考查理解能力的题,对题设中所给的关系进行探究,方可得出正确答案,本题易因为理解不了题意而导致无法下手,题目较抽象.三、解答题:本大题共6小题,共75分.解答应写出文字说明,证明过程或演算步骤. 16.已知集合A={y|y=x2﹣x+1,x∈},B={x|x+m2≥1}.命题p:x∈A,命题q:x∈B,且命题p是命题q的充分条件,求实数m的取值范围.考点:必要条件、充分条件与充要条件的判断.专题:规律型.分析:先求出命题p,q的等价条件,利用p是q的充分,确定实数a的取值范围.解答:解:y=x2﹣x+1=(x﹣),当x∈时,,即A=,B={x|x+m2≥1}={x|x≥1﹣m2},若命题p是命题q的充分条件,则A⊆B,即,∴m,解得m或m.∴实数m的取值范围是m或m.点评:本题主要考查充分条件和必要条件的应用,利用二次函数的性质求出集合A是解决本题的关键.17.已知函数f(x)=Asin(ωx+φ)(x∈R,ω>0,0<φ<)的部分图象如图所示.(Ⅰ)求函数f(x)的解析式;(Ⅱ)将函数f(x)的图象向右平移个单位,得到函数g(x),求g(x)的单调递增区间.考点:由y=Asin(ωx+φ)的部分图象确定其解析式;函数y=Asin(ωx+φ)的图象变换.专题:三角函数的图像与性质.分析:(Ⅰ)由图象知函数的周期,进而可得ω,再由点和(0,1)在函数图象上,可得φ和A,可得解析式;(Ⅱ)由图象变换易得g(x)=2sin(2x﹣),由可得.解答:解:(Ⅰ)由图象知函数的周期,∴,又∵点在函数图象上,∴,即,∵0<φ<,∴<+φ<,∴,解得,又点(0,1)在函数图象上,∴,解得A=2.∴;(Ⅱ)由题知,令,可得∴g(x)的递增区间为:点评:本题考查三角函数的图象与解析式,涉及三角函数图象的变换,属基础题.18.已知定义域为R的函数f(x)=是奇函数.(1)求a,b的值;并判定函数f(x)单调性(不必证明).(2)若对于任意的t∈R,不等式f(t2﹣2t)+f(2t2﹣k)<0恒成立,求k的取值范围.考点:函数恒成立问题;函数单调性的判断与证明.专题:函数的性质及应用.分析:(1)由题意知f(0)=0求出b,再由奇函数的定义求出b;(2)利用奇函数的性质转化为一元二次不等式,借助与一元二次函数的关系进行判断.解答:解:∵定义域为R的函数f(x)=是奇函数,∴,即化简,得解得,∴a的值是2,b的值是1.∴f(x)是R上的减函数;(3)由f(t2﹣2t)+f(2t2﹣k)<0,得f(t2﹣2t)<﹣f(2t2﹣k),∵f(x)是奇函数,∴f(t2﹣2t)<f(k﹣2t2),由(2)知,f(x)是减函数,∴原问题转化为t2﹣2t>k﹣2t2,即3t2﹣2t﹣k>0对任意t∈R恒成立,∴△=4+12k<0,解得k<﹣,所以实数k的取值范围是:k<﹣,点评:本题考查函数的奇偶性、单调性及不等式恒成立问题,定义是解决单调性问题的基本方法,而恒成立问题往往转化为函数最值问题解决.19.现需要对某旅游景点进一步改造升级,提高旅游增加值,经过市场调查,旅游增加值y万元与投入x万元之间满足y=,且∈(Ⅰ)求y=f(x)的解析式和投入x的取值范围;(Ⅱ)求旅游增加值y取得最大值时对应的x值.考点:利用导数求闭区间上函数的最值;利用导数研究函数的单调性.专题:应用题;导数的综合应用.分析:(1)将x=10时,y=9.2代入解析式中即可求得a的值,再由t得出x的取值范围;(2)求出f(x)的导数,对t的取值范围进行讨论,求出单调区间,从而求出函数的最值.解答:解:(Ⅰ)因当x=10时,y=9.2,即,解得.所以,又因为,且,解得即投入x的取值范围是.(Ⅱ)对f(x)求导,得,又因为x>6,所以从广义上讲有,当6<x<50时,f'(x)>0,即f(x)递增,当x>50时,f'(x)<0,即f(x)递减.所以当x=50时为极大值点,也是最大值点,于是①当,即时,投入50万元改造时取得最大增加值;②当时,即时,投入万元改造时取得最大增加值.点评:本题考查了,运用导数求函数的单调区间,最值,分类讨论数学思想,是一道导数的应用题.属于中档题.20.已知函数y=f(x),若存在x0∈R,使f(x0)=x0,则称x0是函数y=f(x)的一个不动点.设二次函数f(x)=ax2+(b+1)x+(b﹣1).(Ⅰ)对任意实数b,函数f(x)恒有两个相异的不动点,求a的取值范围;(Ⅱ)在(Ⅰ)的条件下,若y=f(x)的图象上A,B两点的横坐标是f(x)的不动点,且A,B两点关于直线y=kx+对称,求b的最小值.考点:二次函数的性质.专题:综合题;函数的性质及应用.分析:(Ⅰ)转化为ax2+bx+b﹣1=0有两个不等实根,转化为b2﹣4a(b﹣1)>0恒成立,再利用二次函数大于0恒成立须满足的条件来求解即可.(Ⅱ)利用两点关于直线对称的两个结论,一是中点在已知直线上,二是两点连线和已知直线垂直.找到a,b之间的关系式,整理后在利用基本不等式求解可得.解答:解:(Ⅰ)∵函数f(x)恒有两个相异的不动点,∴f(x)﹣x=ax2+bx+(b﹣1)=0恒有两个不等的实根,∴△=b2﹣4a(b﹣1)=b2﹣4ab+4a>0对b∈R恒成立,∴(4a)2﹣16a<0,得a的取值范围为(0,1).…4分(Ⅱ)由ax2+bx+(b﹣1)=0得,由题知k=﹣1,,…6分设A,B中点为E,则E的横坐标为,…10分∴,∴,当且仅当,即时等号成立,∴b的最小值为.…12分.点评:本题是在新定义下对函数知识的综合考查,是一道好题.关于两点关于直线对称的问题,有两个结论同时存在,一是中点在已知直线上,二是两点连线和已知直线垂直.21.已知函数f(x)=e x﹣ax﹣1(a∈R).(Ⅰ)求函数f(x)的单调递增区间;(Ⅱ)若对一切实数x∈R,都有f(x)≥0恒成立,求a的取值范围.(Ⅲ)求证:,n∈N*.考点:利用导数研究函数的单调性;利用导数求闭区间上函数的最值.专题:导数的综合应用.分析:(Ⅰ)利用导数判断函数的单调性,主要对a进行讨论;(Ⅱ)有f(x)≥0恒成立,转化为求函数f(x)的最小值问题解决,利用导数求函数的最小值即可;(Ⅲ)利用(Ⅱ)的结论得e x≥x+1,令,则有即有,即(当且仅当i=0时取等号),即可得证.解答:解:(Ⅰ)由f′(x)=e x﹣a,①当a≤0时,显然f′(x)=e x﹣a≥0;②当a>0时,由f′(x)=0得x=lna,显然当x>lna时,f′(x)>0;所以当a≤0时,f(x)在R上单调递增;当a>0时,f(x)在(lna,+∞)上递增;(Ⅱ)由(Ⅰ)问知,当a≤0时,f(x)递增,且,不合题意,舍去.当a>0时,由(Ⅰ)知,当x<lna时,f′(x)<0,当x>lna时,f′(x)>0所以当x=lna时,f(x)有极小值也是最小值,即f(x)min=f(lna)=a﹣alna﹣1,依题意a﹣alna﹣1≥0,…①①式可化为,而由超越不等式知:时取到等号),所以比较上下两式可以发现,即a﹣alna﹣1=0(a=1时取到等号),下面给出其证明:令g(a)=a﹣alna﹣1,a>0,则g′(a)=﹣lna,于是g′(a)=0时,a=1,同理知当a=1时,g(a)有极大值也是最大值,所以g(a)≤g(1)=0…②比较①②式可得,g(a)=0,即a=1为所求.(Ⅲ)由(Ⅱ)知对∀x∈R,有e x≥x+1,于是令,则有即有,即(当且仅当i=0时取等号)所以有即,即证.点评:本题考查利用导数研究函数的单调性及最值问题,考查学生恒成立问题的等价转化思想及不等式的证明,注意构造法的合理应用,属于难题.。
湖南省岳阳县第一中学高三10月月考语文试题 Word版含答案.pdf

湖南省岳阳县一中2015届高三10月第二次月考 语文试卷 时量:150分钟 总 分:150分 命题:岳阳县一中 命题人:许柳明 一、语言文字运用(21分,每小题3分) 1. 下列词语中加点的字,读音全都正确的一组是( )勖勉(xù) 殒身不恤(xù)发难(nàn) 排忧解难(nán)戏谑(xuè)沆瀣一气(xiè)吐哺(bǔ) 衡阳之浦(pǔ)鲜见(xiǎn) 屡见不鲜(xiān)毗邻(pí) 纰漏(pī)搠倒(shuò) 横槊赋诗(shuò)目(chēn) 遥岑远目(chén)缱绻(quǎn)蜷缩quán) D.犄角(jī) 掎角之势(jī) 饯别(jiàn) 天梯石栈(zhàn)锃亮(zèng) 憎恶(zēng)下列各组( ) 腥红 歌声茫 舶来品 寥廓 浪遏飞舟 箫索 秋蝉嘶叫 葱茏 繁茂苍翠B.“综合评价”选拔将通过考生自荐、中学校长实名推荐两种方式,根据考生的高考成绩(含加分)(占70%)、中国科学院大学面试成绩(占20%)、高中学业水平考试成绩(占10%)的组合方式,计算出“综合评价”成绩,由高到低择优录取。
C.“十二五”期间,国家将综合运用行政、财政、金融、税收、土地等多种手段和政策措施,以重点工程为抓手,着力推进并谋划文化事业全面繁荣和文化产业大发展。
D.他有说不清的后悔,道不明的愧疚,怎么就和自己同过患难,共过生死的朋友分道扬镳了呢?.给下面一组句子排序正确的一项是( ) 微博的出现,形成了一种不均衡的信息传播态势。
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于是,有一部分微博人以语言新奇、行为离奇、思想极端来炮制轰动效应 这些新闻纷纷扰扰,既耸人听闻又语焉不详,搅乱了百姓的正常生活 由于微博内容只能由当事人把关,于是它成为一些好事者传播“ ④ 所以,每条微博的内容都能够被较多人关注的几率其实很小 但是,人们的注意力是十分有限的 每个微博人都希望自己的情感、观点能在瞬间传播中受人关注,成为微博名人、意见领袖 A. B.④⑤⑥③②① C.①②③④⑤⑥ D.⑤④③②⑥① 6.下面这首宋词《虞美人》(陈与义)中的横线处应填入的最贴切的句子是() 张帆欲去仍搔首,更醉君家酒。
湖南省岳阳县第一中学高三10月月考数学(理)试题

湖南省岳阳县一中2015届高三10月第二次月考数 学(理科)总分:150分 时量:120分钟命题:易正红 审题:唐元波一、选择题:本大题共10小题,每小题5分,共50分.在每小题给出的四个选项中,只有一项是符合题目要求的,请将所选答案填在答题卡中对应位置.1.设集合{1,2,3,4,5,6},{|26}P Q x x ==≤≤,那么下列结论正确的是( )A.B. C. D.2.设, ,则是成立的( )A. 充分不必要条件B. 必要不充分条件C. 充分必要条件D. 既不充分也不必要条件 3.命题“,都有”的否定是( )A.,使得B.,使得C.,使得D.,使得 4.已知扇形的面积为,半径为1,则该扇形的圆心角的弧度数是( )A. B. C. D.5.已知3cos(),(,2)5x x πππ+=∈,则 ( )A .B .C .D . 6.函数的定义域为( )A. B.C. D. 7.若定义在上的函数满足2log (1),0,()(5),0x x f x f x x -≤⎧=⎨->⎩,则 ( ) A. 2 B. 1 C. 0 D. -18.若函数()sin 2(0,0)f x A x A ωω=>>在处取得最大值,则的奇偶性为( )A. 偶函数B. 奇函数C. 既是奇函数又是偶函数D. 非奇非偶函数9.函数25()sin()log 22f x x x π=-的零点个数为( ) A. 1 B. 2 C. 3D. 410.已知两条直线和24:(0,1l y m m m =>≠+,与函数的图象 从左至右相交于点,与函数的图象从左至右相交于点.记线段和在轴上的投影长度分别为,当变化时,的最小值为( )A .B .C .D .二、填空题:本大题共5小题,共25分,把答案填在答题卡中对应题号后的横线上.11.函数的最小正周期为 .12.计算的结果是 .13.已知,且,则 .14.已知函数,若,使得都有,则实数的取值范围是 .15.下图展示了一个由区间到实数集的映射过程:区间中的实数对应数轴上的点,如图1;将线段围成一个圆,使两端点恰好重合(点从点按逆时针方向运动至点),如图2;再将这个圆放在平面直角坐标系中,使其圆心在轴上,点的坐标为,如图3.图3中直线与轴交于点,则的象就是,记作.下列说法中正确命题的序号是 .(填出所有正确命题的序号)①; ②在定义域上单调递增; ③方程的解是;④是奇函数; ⑤的图象关于点对称.三、解答题:本大题共6小题,共75分.解答应写出文字说明,证明过程或演算步骤.16.(本小题满分12分) 已知集合233{|1,[,2]},24A y y x x x ==-+∈.若“”是“”的充分条件,求实数的取值集合...17.(本小题满分12分)已知函数()sin()(,f x A x x R ωϕ=+∈的部分图象如图右所示.(Ⅰ)求函数的解析式;(Ⅱ)将函数的图象向右平移个单位,得到函数,求的单调递增..区间...18.(本小题满分12分)已知定义域为的函数是奇函数.(Ⅰ)求的值,并判断的单调性(不必给出证明......); (Ⅱ)若对任意的,不等式22(2)(2)0f t t f t k -+-<恒成立,求的取值范围.19.(本小题满分13分)现需要对某旅游景点进一步改造升级,提高旅游增加值,经过市场调查,旅游增加值万元与投入万元之间满足且,其中为大于12的常数.当时,. (Ⅰ)求的解析式和投入的取值范围;(Ⅱ)求旅游增加值取得最大值时对应的值.20.(本小题满分13分)已知函数,若存在,使,则称是函数的一个不动点.设二次函数2()(1)(1)f x ax b x b =+++-. (Ⅰ)若对任意实数,函数恒有两个相异的不动点,求的取值范围;(Ⅱ)在(Ⅰ)的条件下,若的图象上两点的横坐标是的不动点,且两点关于直线对称,求的最小值.21.(本小题满分13分)已知函数()1()x f x e ax a R =--∈.(Ⅰ)求函数的单调递.增.区间..; (Ⅱ)若对一切实数,都有恒成立,求的取值范围.(Ⅲ)求证:121()()()()1n n n n n n e n n n n e -++++<-,. 第二次月考参考答案(理数) 一、选择题 D B C C B; A B A C B 二、填空题 11. 1 . 12.. 13.. 14.. 15 ②③⑤ . 三、解答题 16.【解】由223371()2416y x x x =-+=-+, 因为,所以……………………………………………………………4分所以,由,得,所以…………………………………………6分因为“”是“”的充分条件,所以…………………………………………………………………………………9分所以,解得.…………………………………………………10分故实数的取值集合为…………………………………………12分 17.【解】(Ⅰ)由图象知, ,则,………………………………2分又点在函数图象上,即,即 又,故,所以,即…………………………………………………………………4分又点(0,1)在函数图象上,所以,得.所以为所求分(Ⅱ)由题知()()2sin[2()]2sin(2)4463g x f x x x ππππ=-=-+=-…………………………8分 令222232k x k ππππ-≤-≤π+,得5,1212k x k k Z πππ-≤≤π+∈………………………10分 所以的递增区间是5[,],1212k k k Z πππ-π+∈……………………………………12分 【注】若考生未将单调区间写“区间形式”,则应扣除2分!18.【解】(Ⅰ)因是定义在上的奇函数,所以,即,解得,从而有.…………………………………………………………2分又由知,解得,不交待角的范围就直接得出6πϕ=的,应扣除1分经检验当时,为奇函数; ………………………………………5分【注】以特值法求出未写出“检验步骤”的同学,应扣除1分; 又11211(),22221x x x f x x R +-==-+∈++ 显然,随的增大而减小,即在上为减函数. ……………………………………7分 (Ⅱ)由(Ⅰ)知,为奇函数, 所以不等式22(2)(2)0f t t f t k -+-<等价于222(2)(2)(2)f t t f t k f k t -<--=-, 又为上的减函数,所以, 即对一切有成立, 所以,解得,即求. …………………………………………………12分19.【解】(Ⅰ)因当时, ,即2511010ln19.250a ⨯-⨯-=,解得.………2分 所以251()ln 5010010x x f x x =--, 又因为且,解得即投入的取值范围是………………………………………………………6分(Ⅱ)对求导,得25115150(1)(50)()50505050x x x x x f x x x x-+--'=--=-=-, 又因为,所以从广义上讲有,当时, ,即递增,当时, ,即递减.所以当时为极大值点,也是最大值点,于是①当,即时,投入50万元改造时取得最大增加值; …………………10分②当时,即时,投入万元改造时取得最大增加值. ……13分 【注】第(Ⅱ)问若未分类讨论,算出的结果至多只能得3分,即不超过第(Ⅱ)问的一半分.20.【解】(Ⅰ)因函数恒有两个相异的不动点,所以2()(1)0f x x ax bx b -=++-=恒有两个不等的实根,所以224(1)440b a b b ab a ∆=--=-+>对恒成立, ……………………………4分所以,解得,即求.…………………………………………6分(Ⅱ)设两点的横坐标为,由(Ⅰ)知,所以,且由题知211,21k y x a =-=-++,…………………………………8分又由题知的中点在直线上,即,显然点也在直线上,于是,………………………………10分可化为21121214222ab a a a =-=-≥-=-++, 当且仅当,即时上式取等号,所以的最小值为.…………………………………………………………………13分【注】第(Ⅱ)问若未说明取最小值的条件,则至少要扣除1分.21.【解】(Ⅰ)由,.………………………………………………………………1分①当时,显然;②当时,由得,显然当时,;所以当时,在上单调递增;当时,在上递增;.……………………………………………………4分(Ⅱ)由(Ⅰ)问知,当时,递增,且,不合题意,舍去.……5分当时,由(Ⅰ)知,当时, ,当时,所以当时,有极小值也是最小值,即min ()(ln )ln 1f x f a a a a ==--,依题意,…①……………………………………………………………7分令()ln 1,0g a a a a a =-->,则,于是时, ,同理知当时,有极大值也是最大值,所以……②比较①②式可得, ,即为所求. …………………………………………10分(Ⅲ)由(Ⅱ)知对,有, 于是令,,,ix n N i N i n n+=-∈∈≤,则有即有,即 (当且仅当时取等号)所以有1210112111111()()()()()()()()1nn n n n n n n n e n n n n e e e e e ------++++<++++=- 即1112111()()()()111n n n n n n n e e n n n n e e e -----++++<<=---,即证. …………………13分。
湖南省岳阳市岳阳一中2015届高三年级第三次月考试卷及答案
岳阳县一中2015届高三年级第三次月考试卷理科数学时量:120分钟 总分:150分一、选择题:本大题共10小题,每小题5分,共50分.在每小题给出的四个选项中,只有一项符合题目要求.1. 设复数11i z =+,22i ()z x x R =+∈,若12R z z ⋅∈,则x =( )A .1-B .2-C .1D .2 2. 下列函数中,既是奇函数又存在极值的是( )A. 3y x =B. ln()y x =-C. e x y x -=D.2y x x=+3. 在ABC 中,15,10,60a b A ===︒,则cos B 等于( )A.C.4. 已知n {a }为等差数列,其前n 项和为S n ,若9S =12,则下列各式一定为定值的是( )A.38a a +B.10aC.357a a a ++D. 27a a +5. 已知()3sin f x x x π=-,命题:0,,()02p x f x π⎛⎫∀∈< ⎪⎝⎭,则 ( )A .p 是假命题;:0,,()02p x f x π⎛⎫⌝∀∈≥ ⎪⎝⎭B .p 是假命题;00:0,,()02p x f x π⎛⎫⌝∃∈≥ ⎪⎝⎭C .p 是真命题; :0,,()02p x f x π⎛⎫⌝∀∈> ⎪⎝⎭D.p 是真命题;00:0,,()02p x f x π⎛⎫⌝∃∈≥ ⎪⎝⎭6. 设等比数列n {a }的前n 项和为n S ,若633,S S = 则 96S S =( )A. 2B.73C. 83D.3 7. 函数44sin cos y x x =+是A .最小正周期为2π,值域为⎤⎥⎣⎦的函数 B .最小正周期为4π,值域为⎤⎥⎣⎦的函数 C .最小正周期为2π,值域为1,12⎡⎤⎢⎥⎣⎦的函数D .最小正周期为4π,值域为1,12⎡⎤⎢⎥⎣⎦的函数 8. 如上图,面积为8的平行四边形,OABC 对角线AC CO ⊥,AC 与BO 交于点E ,某指数函数()0,1x y a a a =>≠且,经过点,E B ,则a =( )C.2D.39. 已知1,1x y >>,且11ln ,,ln 44x y 成等比数列,则xy 的最小值是( )A. 1B.1eC. eD. 210. 已知函数e ()e 1x x mf x +=+,若对于任意,,a b c ∈R ,都有()()()f a f b f c +>成立,则实数m 的取值范围是 ( )A.1[,2]2B.[0,1]C.[1,2]D.1[,1]2二、 填空题:本大题共5小题,每小题5分,共25分.11. 已知集合{}{}()R |,|12,RA x x aB x x A B =<=<<= 且ð,则实数a 的取值范围是 .12. 数列{}n a 中,()11+21,,N 2nn n a a a n a +==∈+,则5a = . 13. 已知()1tan ,0,43πααπ⎛⎫+=∈ ⎪⎝⎭,则sin α= . 14. 平面向量,,a b e满足: 1e = ,1,2,2a e b e a b ==-=,则向量a b - 与e 的夹角 第8题图为 .15.的范围是 ..三、解答题:本大题共6个小题,共75分,解答题写出文字说明、证明过程或演算步骤. 16. (本小题满分12分)在正项等比数列{}n a 中, 公比()0,1q ∈,且满足32a =,132435225a a a a a a ++=. (1)求数列{}n a 的通项公式;(2)设n n a b 2log =,数列{}n b 的前n 项和为n S ,当nS S S n +⋅⋅⋅++2121取最大值时,求n 的值.17.(本小题满分12分)在ABC ∆中,内角,,A BC 所对的边分别是,,a b c . 已知3a =,cos A =,2B A π=+. (1)求b 的值; (2)求ABC ∆的面积.18.(本小题满分12分)设约束条件021(01)y y x y x t x t t ≥⎧⎪≤⎪⎨≤-⎪⎪≤≤+<<⎩所确定的平面区域为D .(1)记平面区域D 的面积为S =f (t ),试求f (t )的表达式.(2)设向量()()1,1,2,1a b =-=-,(),Q x y 在平面区域D (含边界)上,,OQ ma nb =+(,)m n R ∈,当面积S 取到最大值时,用y x ,表示3m n +,并求3m n+的最大值.19. (本小题满分13分)已知111)(111)(++-+=++++=x x xx x g x x x x x f 及(1)求()f x 的最小值和()g x 的最大值; (2)若1,,12+==++=x c x t b x x a ,问是否存在满足下列条件的正数t ,使得对于任意的正数,,,x a b c 都可以成为某个三角形三边的长?若存在,则求出t 的取值范围;若不存在,请说明理由.20. (本小题满分13分)若数列{}n a 的前n 项和为n S ,对任意正整数n 都有612n n S a =-. (1)求数列{}n a 的通项公式; (2)令()11112241(1)log log n n n n n b a a -++=-∙,求数列{}n b 的前n 项和n T .21. (本小题满分13分)已知函数2()ln()g x x x a =++,其中a 为常数. (1)讨论函数()g x 的单调性; (2)若()g x 存在两个极值点12,x x ,求证:无论实数a 取什么值都有()()121222g x g x x x g ++⎛⎫> ⎪⎝⎭.。
湖南省岳阳县一中、湘阴县一中2015届高三12月联考数学(文)试题
湖南省岳阳县一中、湘阴县一中2015届高三12月联考数学(文)试题时量:150分钟 分值:150分一、选择题:本大题共10个小题,每小题5分,共50分,在每小题给出的四个选项中有且只有一项是符合题目要求的.1、已知集合{14,},{15}A x x x Z B x x =-≤≤∈=<<,则AB =( )A .{14}x x <≤B .{2,3,4}C .{1,0,1,2,3,4}-D .{15}x x -≤< 2、若sin 0α<且tan 0α>,则α是( )A .第一象限角B .第二象限角C .第三象限角D .第四象限角 3、已知等差数列{}n a 的前n 项和为n S ,6312a S ==,则4a =( )A .4B .6C .8D .104、某几何体的三视图如图所示,其中正视图和左视图是边长为2的等边三角形,则该几何体的体积等于( ) AC .23π D.35、已知,p q 是两个命题,则“p q ∨为真命题”是“p q ∧为真命题”的( ) A .充分不必要条件 B .必要不充分条件C .充分必要条件D .既不充分也不必要条件 6、已知()f x 是周期为4的奇函数,(3)2f =,则(9)f =( )A .6B .6-C .2D .2- 7、已知向量,a b 满足2,3a b ==,且()6a b b +=,则a 与b 的夹角为( ) A .6π B .4π C .3π D .2π 8、已知数列{}n a 满足123()n n a a n N *++=∈,且17a =,其前n 项和为n S ,则满足不等式142014n S n --<的最小整数n 是( ) A.11 B .12 C .13 D .149、记曲线sin,[3,1]2y x x π=∈-与1y =所围成的封闭区域为D ,若直线2y ax =+与D有公共点,则实数a 的取值范围是( )A .1[1,]3-B .1(,1][,)3-∞-+∞ C .11[,]3ππ-D .11(,][,)3ππ-∞-+∞ 10、用min{,}a b 表示,a b 两数中的最小值,函数()min{2,2}f x x x t =+的图象关于直线1x =-对称,若方程()f x m =恰有4个不相等的实数根,则实数m 的取值范围为( )A .(0,1]B .(0,1)C .(0,2]D .(0,2)二、填空题:本大题共5个小题,共25分,将答案填写在题中的横线上.11、若直线3450x y +-=与圆224x y +=相交于,A B 两点,则弦AB 的长等于 .12、在ABC ∆中,43A AC π==,,其面积S =BC = .13、底面半径为3cm 的圆柱体水槽中有半槽水,现放入两个直径等于水槽底面圆直径的球,若水槽中的水刚好满了,则水槽的高是 cm . 14、若不等式22sin 2cos 32(0)x a x a a a +≤+-<对一切x R ∈恒成立,则实数a 的最大值是 .15、已知函数()12,[0,1]f x x x =-∈,记1()()f x f x =,且1()[()],n n f x f f x n N *+=∈.(1)若函数()y f x ax =-仅有2个零点,则实数a 的取值范围是 . (2)若函数2()log (1)n y f x x =-+的零点个数为n a ,则满足2(12)n a n <+++的所有n 的值为 .三、解答题:本大题共6个小题,共75分,解答应写出文字说明,证明过程或演算步骤.16、(本小题满分12分)已知向量(23sin ,cos2),(cos ,1)(0)a x x b x ωωωω==->,函数()f x a b =,且其图象的两条相邻对称轴之间的距离是4π. (Ⅰ)求ω的值;(Ⅱ)将函数()f x 图象上的每一点的横坐标伸长到原来的2倍,纵坐标不变,得到函数()g x 的图象,求()y g x =在区间[0,]2π上的最大值和最小值.17、(本小题满分12分)如图,在各棱长都相等的直三棱柱111ABC A B C -中,,E F 分别为1,AB CC 的中点. (Ⅰ)求证://CE 平面1AB F ;(Ⅱ)求直线1A F 与平面1AB F 所成角的正弦值18、(本小题满分12分)山区一林场2013年底的木材存量为30万立方米,森林以每年20﹪的增长率生长.从今年起每年年底要砍伐1万立方米的木材,设从今年起的第n 年底的木材存量为n a 万立方米.(Ⅰ)试写出1n a +与n a 的关系式,并证明数列{5}n a -是等比数列; (Ⅱ)问大约经过多少年,林场的木材总存量达到125万立方米? (参考数据:lg 20.30,lg30.48==)19、(本小题满分13分)已知函数21(),1()23,1xx f x x x x ⎧<-⎪=⎨⎪+≥-⎩.(Ⅰ)解不等式()4f x <;(Ⅱ)当[1,2]x ∈-时,()2()f x mx m R ≥-∈恒成立,求实数m 的取值范围. 20、(本小题满分13分)各项均为正数的数列{}n a ,其前n 项和为n S ,且满足11a >,2632n n n S a a =++. (Ⅰ)求数列{}n a 的通项公式;(Ⅱ)若数列{}n b 前n 项和为n T ,且满足211932n n n n a T a T n n ++=--+.问1b 为何值时,数列{}n b 为等差数列; (Ⅲ)23a +>.21、(本小题满分13分)设函数()ln (0)f x x mx m =->. (Ⅰ)求函数()f x 的单调区间;(Ⅱ)判断函数()f x 在区间[1,]e 上的零点个数.岳阳县一中湘阴县一中高三月考联考试卷数学(文)时量:150分钟 分值:150分参考答案一、选择题:本大题共10个小题,每小题5分,共50分,在每小题给出的四个选项中有且只有一项是符合题目要求的.1、已知集合{14,},{15}A x x x Z B x x =-≤≤∈=<<,则AB =( B )A .{14}x x <≤B .{2,3,4}C .{1,0,1,2,3,4}-D .{15}x x -≤< 2、若sin 0α<且tan 0α>,则α是( C )A .第一象限角B .第二象限角C .第三象限角D .第四象限角 3、已知等差数列{}n a 的前n 项和为n S ,6312a S ==,则4a =( C )A .4B .6C .8D .104、某几何体的三视图如图所示,其中正视图和左视图是边长为2的等边三角形,则该几何体的体积等于( A ) AC .23π D.35、已知,p q 是两个命题,则“p q ∨为真命题”是“p q ∧为真命题”的( B ) A .充分不必要条件 B .必要不充分条件C .充分必要条件D .既不充分也不必要条件 6、已知()f x 是周期为4的奇函数,(3)2f =,则(9)f =( D )A .6B .6-C .2D .2- 7、已知向量,a b 满足2,3a b ==,且()6a b b +=,则a 与b 的夹角为( A ) A .6π B .4π C .3π D .2π 8、已知数列{}n a 满足123()n n a a n N *++=∈,且17a =,其前n 项和为n S ,则满足不等式142014n S n --<的最小整数n 是( C ) A.11 B .12 C .13 D .149、记曲线sin,[3,1]2y x x π=∈-与1y =所围成的封闭区域为D ,若直线2y ax =+与D有公共点,则实数a 的取值范围是( B )A .1[1,]3-B .1(,1][,)3-∞-+∞ C .11[,]3ππ-D .11(,][,)3ππ-∞-+∞ 10、用min{,}a b 表示,a b 两数中的最小值,函数()min{2,2}f x x x t =+的图象关于直线1x =-对称,若方程()f x m =恰有4个不相等的实数根,则实数m 的取值范围为( D )A .(0,1]B .(0,1)C .(0,2]D .(0,2)二、填空题:本大题共5个小题,共25分,将答案填写在题中的横线上.11、若直线3450x y +-=与圆224x y +=相交于,A B 两点,则弦AB 的长等于 .12、在ABC ∆中,43A AC π==,,其面积S =BC = .13、底面半径为3cm 的圆柱体水槽中有半槽水,现放入两个直径等于水槽底面圆直径的球,若水槽中的水刚好满了,则水槽的高是 cm .16 14、若不等式22sin 2cos 32(0)x a x a a a +≤+-<对一切x R ∈恒成立,则实数a 的最大值是 .2-15、已知函数()12,[0,1]f x x x =-∈,记1()()f x f x =,且1()[()],n n f x f f x n N *+=∈.(1)若函数()y f x ax =-仅有2个零点,则实数a 的取值范围是 .(0,1] (2)若函数2()log (1)n y f x x =-+的零点个数为n a ,则满足2(12)n a n <+++的所有n 的值为 .2,3,4三、解答题:本大题共6个小题,共75分,解答应写出文字说明,证明过程或演算步骤.16、(本小题满分12分)已知向量(23sin ,cos2),(cos ,1)(0)a x x b x ωωωω==->,函数()f x a b =,且其图象的两条相邻对称轴之间的距离是4π. (Ⅰ)求ω的值;(Ⅱ)将函数()fx 图象上的每一点的横坐标伸长到原来的2倍,纵坐标不变,得到函数()g x 的图象,求()y g x =在区间[0,]2π上的最大值和最小值.解:(Ⅰ)由题()f x a b =cos cos2x x x ωωω=-2sin(2)6x πω=-…3分又()f x 的周期242T ππ=⨯=所以222ππω=,即2ω= ………………………………………………6分 (Ⅱ) 由(Ⅰ) 得()2sin(4)6f x x π=-又由题意得()2sin(2)6g x x π=-………………………………………8分因为[0,]2x π∈,所以52[,]666x πππ-∈- 当266x ππ-=-即0x =时,min ()1g x =-当262x ππ-=即3x π=时,max ()2g x = ………………………………12分17、(本小题满分12分)如图,在各棱长都相等的直三棱柱111ABC A B C -(Ⅰ)求证://CE 平面1AB F ;(Ⅱ)求直线1A F 与平面1AB F 所成角的正弦值.证明:(Ⅰ)如图示,连接1A B 交1AB 于D 由题DE 是1ABB ∆的中位线∴1//DE BB 且112DE BB =即//DE CF 且DE CF = ∴四边形DECF 为平行四边形∴//CE DF又CE ⊄平面1AB F ,DF ⊂平面1AB F∴//CE 平面1AB F …………………6分解:(Ⅱ)∵直三棱柱111ABC A B C -各棱长都相等,E 为AB 的中点∴1,CE AB CE AA ⊥⊥∴CE ⊥平面11ABB A ,又1A B ⊂平面11ABB A ∴1CE A B ⊥ 由(Ⅰ) //CE DF 得1DF A B ⊥又11A D AB ⊥,1,DF AB 是平面1AB F 内两条相交直线∴1A D ⊥平面1AB F∴DF 是1A F 在平面1AB F 上的射影∴1A FD ∠是1A F 与平面1AB F 所成的角 ……………………………9分 设直三棱柱111ABC A B C -的棱长为a 在1Rt A DF ∆中,11,A D A F ===∴111sin 5A D A FD A F ∠==∴直线1A F 与平面1AB F所成角的正弦值是5……………………12分 18、(本小题满分12分)山区一林场2013年底的木材存量为30万立方米,森林以每年20﹪的增长率生长.从今年起每年年底要砍伐1万立方米的木材,设从今年起的第n 年底的木材存量为n a 万立方米.(Ⅰ)试写出1n a +与n a 的关系式,并证明数列{5}n a -是等比数列; (Ⅱ)问大约经过多少年,林场的木材总存量达到125万立方米? (参考数据:lg 20.30,lg30.48==) 解:(Ⅰ)由题得1(120%)1n n a a +=⨯+-即1615n n a a +=- ……………………………………………………2分 所以166565555n n n n a a a a +--==-- 因此数列{5}n a -是公比为65的等比数列 …………………………6分 (Ⅱ)由题1530(120%)1530a -=⨯+--=所以16530()5n n a --=,即1630()55n n a -=+ …………………………8分 所以1630()51255n n a -=+≥,即16()45n -≥6(1)lg lg 45n -≥所以2lg 218.52lg 2lg31n >+=+-所以,大约经过9年,林场的木材总存量达到125万立方米 …………12分19、(本小题满分13分)已知函数21(),1()23,1xx f x x x x ⎧<-⎪=⎨⎪+≥-⎩.(Ⅰ)解不等式()4f x <;(Ⅱ)当[1,2]x ∈-时,()2()f x mx m R ≥-∈恒成立,求实数m 的取值范围. 解:(Ⅰ)当1x <-时由21()2422x x-=<=得2x >-所以21x -<<- …………………………………………………2分 当1x ≥-时由234x x +<得41x -<<所以11x -≤< …………………………………………………4分 综上,原不等式的解集是{21}x x -<< ……………………………5分(Ⅱ) 由题意得232x x mx +≥-即232mx x x ≤++在[1,2]-上恒成立(ⅰ)当0x =时,232mx x x ≤++恒成立,所以m R ∈ ………………6分 (ⅱ) 当[1,0)x ∈-时,原不等式变形为23m x x≥++ 设2()3,[1,0)g x x x x=++∈-因为当[1,0)x ∈-时,'22()10g x x =-=< 所以()g x 在[1,0)-上单调递减当1x =-时,max ()(1)0g x g =-=所以0m ≥ ……………………………………………………………9分 (ⅲ) 当(0,2]x ∈时,原不等式变形为23m x x≤++又233x x++≥当x =min 2(3)3x x++=所以3m ≤ …………………………………………………12分综上所述,实数m 的取值范围是3] ………………………13分20、(本小题满分13分)各项均为正数的数列{}n a ,其前n 项和为n S ,且满足11a >,2632n n n S a a =++. (Ⅰ)求数列{}n a 的通项公式;(Ⅱ)若数列{}n b 前n 项和为n T ,且满足211932n n n n a T a T n n ++=--+.问1b 为何值时,数列{}n b 为等差数列;(Ⅲ)23a +>. 解:(Ⅰ)由题 2632n n n S a a =++ ①得 2111632n n n S a a +++=++ ②②-①得 22111633n n n n n a a a a a +++=+--即 11()(3)0n n n n a a a a +++--= …………………………2分因为0n a >,所以13n n a a +-=又1n =时,2111632a a a =++即11(1)(2)0a a --=又11a >,12a =所以31n a n =- ………………………………………………4分(Ⅱ)由(Ⅰ)及题意得21(31)(32)932(31)(32)n n n T n T n n n n +--+=-+=-+ 即113231n n T T n n +-=+- 所以数列{}31n T n -是以12T 为首项,以1为公差的等差数列 ………6分 所以11312n T T n n =+-- 即1(1)(31)2n T T n n =+-- 若数列{}n b 为等差数列,则1102T -=,即12T =所以12b =.(此时64n b n =-) ……………………………8分(Ⅲ)由(Ⅰ)及题意得==>3= ………11分2(52853231)3n na +>-+-+++--23a ++> ……………………13分 21、(本小题满分13分)设函数()ln (0)f x x mx m =->. (Ⅰ)求函数()f x 的单调性;(Ⅱ)判断函数()f x 在区间[1,]e 上的零点个数.解:(Ⅰ)由题得1()1()(0,0)m x m f x m x m x x --'=-=>> ………………2分 当10x m <<时,()0f x '>;当1x m>时,()0f x '< 所以函数()f x 的单调递增区间是1(0,)m ,单调递减区间是1(,)m+∞ ……5分 (Ⅱ)由(Ⅰ)知函数()f x 在1(0,)m 上单调递增,在1(,)m+∞上单调递减 所以函数()f x 在区间[1,]e 上最多有2个零点而且max 11()()ln 1f x f m m==-,(1)0f m =-< …………………6分 (ⅰ)若函数()f x 在区间[1,]e 上有2个零点则()0111()00f e e m f m m ≤⎧⎪⎪<<⎪⎨⎪>⎪⎪>⎩,此不等式组无解所以不存在0m >,使函数()f x 在区间[1,]e 上有2个零点 ………8分 (ⅱ) 若函数()f x 在区间[1,]e 上仅有1个零点则()00f e m ≥⎧⎨>⎩,解得10m e <≤ 所以当10m e <≤时,函数()f x 在区间[1,]e 上仅有1个零点 ………10分 (ⅲ) 若函数()f x 在区间[1,]e 上无零点结合(ⅱ)知1m e>,即10e m << 则()01()00f e f mm <⎧⎪⎪<⎨⎪>⎪⎩,解得1m e > 所以当1m e>时,函数()f x 在区间[1,]e 上无零点 …………………12分 综上所述,当10m e<≤时,函数()f x 在区间[1,]e 上有1个零点 当1m e >时,函数()f x 在区间[1,]e 上无零点 ……………13分。
湖南省岳阳县一中2015届高三10月第二次阶段考试英语试卷及答案
岳阳县一中2015届高三年级第二次月考试卷英语时量:120分钟总分:150分Part I Listening Comprehension (30 marks)Section A (22.5 marks)Directions: In this section, you will hear six conversations between two speakers. For each conversation, there are several questions and each question is followed by three choices marked A, B and C. Listen carefully and then choose the best answer for each question.You will hear each conversation TWICE.Conversation 11. What’s wrong with the man?A. He has a headache.B. He has a stomachache.C. He has a pain in the back.2. Where is the man probably?A. At home.B. At a drugstore.C. At a hospital.Conversation 23. What will Mr Brown do after lunch?A. Go back to the office.B. Attend a meeting.C. Go to an exhibition.4. What will the man do?A. Call back later.B. Wait for Mr Brown at the office.C. Write a letter to Mr Brown.Conversation 35. What is the woman’s destination?A.1323 Yingze StreetB. 3023 Yingze Street.C. 2023 Yingze Street.6. Who is the man?A. A bus driver.B. The woman’s friend.C. A taxi driver.Conversation 47. What will the woman go home for?A. A wedding.B. A holiday.C. A birthday.8. How will the woman go to the airport?A. By taxi.B. By subway.C. By bus.9. What will the woman do next?A. Make a reservation.B. Buy a ticket.C. Have dinner with the man.Conversation 510. How long has the man been lost?A. About 10 minutes.B. About 30 minutes.C. About an hour..11. Where will the man go?A. A train station.B. A bank.C. The woman’s house.12. What will the man do?A. Find the way himself.B. Go to the supermarket.C. Wait for the woman to come.Conversation 613. What major does the man want to take?A. English.B. Math.C. Mechanical Engineering.14. At what kind of schools can the man get a scholarship probably?A. The average schools.B. The good schools.C. The school in his own country.15. What will the woman help the man do?A. Buy a ticket.B. Learn the English.C. Apply for some schools.Section B (7.5 marks)Directions: In this section, you will hear a short passage. Listen carefully and then fill in the numbered blanks with the information you have heard. Fill in each blank with NO MORE THAN THREE WORDS.Part II Language Knowledge (45 marks)Section A (15 marks)Directions: Beneath each of the following sentences there are four choices marked A, B, C and D. Choose the one answer that best completes the sentence.21. Those _____ cannot answer all three riddles will be condemned to death.A. thatB. whoC. whichD. what22. --- Do you often feel anxious and uncomfortable?--- No, but I __________.A. didn’tB. used to beC. used toD. wasn’t23. ____ a peasant boy of no more than seventeen, who was badly wounded.A. Seated in the corner wasB. Was seated in the cornerC. In the corner was seatingD. In the corner was seated24. Mr White is opposed to repairing the old building, and that’s ______ I don’t agree.A. whichB. thatC. whereD. what25. __________ he does has nothing to do with me.A. IfB. No matter whatC. ThatD. whatever26. ---_______ the farmers discovered the entrance to the secret cave in the valley?--- Totally by chance.A. When was itB. How was itC. How was it thatD. When was it that27. The fact ____ ancient Greek civilization had a great influence on Western culture is known to manypeople.A. whetherB. thatC. ifD. how28. We live in a society ______ there is a great deal of debate about competition.A. whereB. whichC. whenD. that29. He made up his mind to devote all he could _____ his spoken English before going to college.A. to be practicingB. practicingC. practiceD. to practicing30. Keep away from the dog , _______it will bite you.A. andB. soC. orD. but31. Stand _____ you are, and I will come and help you.A. whileB. whereC. whichD. what32. The old man turned his business over to his younger son, ________made his elder son discouraged.A. whoB. whatC. thatD. which33. He hasn’t decided _____ he will go abroad next year.A. whetherB. whenC. whereD. why34. He was fortunate ____ he did not get injured in the car accident.A. but thatB. except thatC. because of thatD. in that35. Only when he returned home ______ what had happened.A. did he realizeB. he realizedC. he did realizeD. has he realizedSection B (18 marks)Directions: For each blank in the following passage there are four words or phrases marked A, B, C and D. Fill in each blank with the word or phrase that best fits the context.What is real success? I am sure many would come up with answers like lots of money, a big house, a new car, and so on.It has been interesting to see how my own idea of success has 36 through the years. When I was young, I was eagerly reaching for material success. I chose my jobs accordingly and ended up in 37 . Sure enough, I did earn some pretty good pay checks.But then a different feeling started to 38 . I began to realize selling was not what I wanted to doall my life. After all I was often forced to sell products that did not really suit customers. All that matters is the amount of money that is made. 39 I became very unhappy.I came to realize that even with big pay checks I did not feel successful. That is when my search for success turned inwards, I 40 sales and chose another profession–helping people. The feeling of relief and belonging was great–and suddenly I felt successful again. Even though I earned 41 than before, I was much more content.Then I returned to my old love–writing.I realized I felt most successful when I loved what I did never 42 the money. Then for my own43 I define success by the feeling of contentment.Always remember–you are not here to 44 anyone else’s life but your own. It is not your obligation (义务) to please others with your life – only yourself, because only if you are happy yourself can you 45 happiness to others. You cannot give what you do not have.So be true to yourself and 46 your own joyful path to your own 47 of success.36. A. occurred B. developed C. completed D. produced37. A. sales B. service C. manufacturing D. tourism38. A. change B. end C. leave D. grow39. A. Eventually B. Randomly C. Fortunately D. Occasionally40. A. undertook B. continued C. experienced D. quit41. A. less B. more C. much D. little42. A. spending B. donating C. minding D. speaking43. A. point B. angle C. part D. interest44. A. influence B. live C. disturb D. practice45. A. spread B. lead C. link D. lend46. A. pass B. cross C. remove D. follow47. A. significance B. definition C. imagination D. limitSection C (12 marks)Directions: Complete the following passage by filling in each blank with one word that best fits the context.Sports are an important part of the society. Sports come in many sizes.Golf is 48 individual sport. Even though golfers play on the same course, 49 are just competing against one another with their scores. Golf is different from tennis. A tennis player must beat the other to finish a match, 50 a golfer needs to play against every other player. The one 51 takes the fewest strokes(击球)to make the ball into 18 holes will be the winner.Baseball, basketball, and soccer are team sports. Team members help each other to win as a team. Sports are played for fun and for money. About every sport has 52 professionals and amateurs.Sports bring people together and also set people apart. They bring people together as a team and make many fans to cheer for that team. And each team has 53 own fans. 54 when two teams compete against each other or two individual athletes compete against each other, the fans are divided 55 two parts.Part III Reading Comprehension (30 marks)Directions: Read the following three passages., Each passage is followed by several questions or unfinished statements. For each of them there are four choices marked A, B,C and D. Choose the one that fits best according to the information given in the passage.A“Iris scan (虹膜扫描), please,” the bank’s computer voice tells you. You step up and the computer reads your eye, comparing it to the stored file it has of your iris. The images had better match---otherwise, you won’t be able to get your money.Iris scanning and other technologies, such as fingerprint and voice scanning, have appeared in many science fiction movies in the past. Today, these advanced technologies are part of the real world. They are common at work, the bank, the airport, and your local prison. The iris scan, fingerprint scan, and voice scan are all examples of biometrics(生物测定学), a fast developing area of automatic personal identification technology. Basically, biometrics uses various ways to verify a person’s identity, based on the individual’s unique characteristics, including fingerprints, signature, and so on.Biometrics identification systems have a number if advantages over password systems. The primary advantage is that an individual has to be physically present in order to be identified. Another important advantage is that there are no passwords to remember, forget, lose, or steal.The voice scan is the simplest and most affordable form of biometrics. It only requires a computer, a microphone, and the correct software. The software records a subject’s voice and then compares it to a stored voice sample for identification purpose.For additional safety, fingerprint and handprint scans can also be employed. Fingerprint scans take the image of a fingerprint and compare it to a stored file of prints. Handprint scans identify the unique features of a hand.56. The first paragraph serves as a(n) ________.A. exampleB. explanationC. commentD. conclusion57. The underline word “verify” in Paragraph 2 probably means “________”.A. protectB. confirmC. developD. change58. Which is the most accurate form of biometrics?A. The voice scanB. The fingerprint scanC. The iris scanD. The facial scan59. What is the author’s attitude towards the future of biometrics?A. He is uncertain about it.B. He feels doubtful about it.C. He is worried about it.D. He feels hopeful about it.60. What is the author’s purpose in writing the text?A. To explain the importance of identification technology.B. To discuss the potential of biometrics systems.C. To introduce the technology of biometrics.D. To show the advantages of iris scanning.BErica McElrath calls herself “ The Happy Lady”. And by now, you may have caught her singing and dancing with her mp3 player on any of several city street corners. “ I don’t want money,” said McElrah, 40, of St. Louis. “ I come out here to make people smile.”McElrah lost her full-time job in January. Since then, she has spent her days doing what she loves-dancing in the street. Her message to people in hard times: do something that you enjoy, no matter what your circumstances. “Life isn’t that bad,”she said. “If you’re working 40 hours a week, you shouldn’t be complaining.”McElrah graduated from parkway Central High School and has spent the past 21 years working as a nursing assistant, She began singing and dancing publicly on her days off a few years ago to help her through the pain of her second divorce.Her favorite spot is the northwest corner of Chouteau Avenue and South Grand Boulevard near St. Louis University. McElrah’s mp3 player is loaded with hundreds of classic rock hits and 80’s pop songs, including those by Joe Cocker, Tina Turner, Neil Diamond and Toto. But her favorite artist, by far, is Stevie Nicks.Videos of McElrah have appeared on YouTube, a video-sharing website on which users can upload, share, and view videos. “People think I’m crazy, but I don’t care,” She said. “ I can dance a little. I just go with the music.” Even a rude gesture from a passing motorist doesn’t bother her either. “ I just smile and wave,” she said.McElrah’s show of bravery recently earned her a job opportunity with Liberty Tax Service, which temporarily offered her a job as a dancer Statute of Liberty to promote a new place near Grand Center starting in January.“ Just be happy and do what you love,” she said. “The money will come.”61. At first McElrah began singing and dancing in public in order to _____.A. make a livingB. entertain the publicC. rise to fameD. encourage herself62. Erica McElrah’s actions are _______.A. popular with othersB. stopped by her familyC. supported by passers-byD. laughed at sometimes63. Erica McElrah was offered a job because of _____.A. her beautiful voiceB. her positive behaviorC. her lively dancingD. her competitive spirit64. Which of the following about Erica McElrah is TRUE?A. She doesn’t care others’ comments on her.B. Her favorite artist is Joe Cocker.C. She once worked as a doctor.D. She has been divorced once.65. What would be the best title for the passage?A. Ways To Be HappyB. Learn To Do What You LoveC. Happy Lady’s Singing and Dancing LifeD. What Made The Happy Lady Famous?CA lot of people are afraid spiders(蜘蛛)–even the small ones. But a big tarantula(鸟蛛)is much more terrifying for many. Now, scientists in Sri Lanka have discovered a huge species of tarantula that’s about the size of a person’s face.The first part of the spider’s scientific name, Poecilotheria rajaei, comes from the Greek words for “spotted”(poikilos) and “wild beast” (therion). Its species name, rajaei, comes from a local police officer who helped the team that discovered the creature. Poecilotheria rajaei has 8-inch long legs, and unusual spots colored gray, pink, and yellow.Although it is very big, is there a real reason to be afraid of one? Maybe. This tarantula has enough poisonous fluid(毒液)to kill mice and small birds and snakes –but its bite wouldn’t cause the death of most humans.Poecilotheria rajaei was first seen in 2009, when a villager in Sri Lanka found the body of a male and brought it to Ranil Nanayakkara, co-founder of Sri Lanka’s Biodiversity Education and Research organization.An examination of the awesome creature proved that it was a type of tarantula scientists hadn’t seen before. So Nanayakkara carefully looked through the Sri Lankan forests to try to find more of the spiders.It’s still too early to know whether this species is endangered. But researchers fear that the tarantulas’natural habitat is slowly being destroyed.“They prefer old trees, but due to the widespread removal of trees the number has dropped,”Nanayakkara said in an interview.Tarantulas have eight legs and two body parts. They are different from insects, which have only six legs but three body parts. Tarantulas have hairy bodies and are usually larger than other types of spiders. Some species of tarantulas can live up to 25 years.While Poecilotheria rajaei is very big, the largest tarantula is the Goliath bird-eater (Theraphosa blondi). Found in the rainforests of South America, its legs can be up to 10 inches long. But don’t worry if you ever see one: Its poisonous fluid isn’t really dangerous to humans.66. According to the text, Poecilotheria rajaei _______.A. has unique spotsB. is mostly yellowC. has 10-inch long legsD. was first seen by the Greeks67. Which of the following is most likely to survive a bite from Poecilotheria rajaei?A. A little girlB. A small bird.C. A big mouse.D. A small snake.68. The number of Poecilotheria rajaei has dropped because___________.A. the global climate has changedB. they have too many natural enemiesC. some people are killing them illegallyD. more and more forests are disappearing69. Which of the following is TRUE about tarantulas?A. They are a kind of insect.B. Most of them live in South America.C. Their body is divided into three parts.D. They are usually of bigger size than other spiders.70. Which section of a newspaper is the text most probably taken from?A. LifeB. NatureC. ScienceD. BusinessPart 1V Writing (45 marks)Section A (10 marks)Directions: Read the following passage. Fill in the numbered blanks by using the information from the passage.Write NO MORE THAN THREE WORDS for each answer.Every person needs energy to go about the day and continue to function correctly. To get this energy, you eat, and your body changes the food into the nutrients and energy you need to survive. Your metabolism (新陈代谢) is directly related to how quickly and efficiently your body creates this energy, and if it takes too long, the food gets stored as fat. A slow metabolism will leave you with less energy and more weight than you probably desire.Your basal metabolic rate (基础代谢率) is the amount of energy your body consumes while you're resting. When people say they have a slow metabolism, they mean they have a slow basal metabolic rate. Increasing this number is possible through exercise and muscle building.According to Metabolism-Advice. com, as your age, your basal metabolic rate will lower as your body begins to deteriorate (衰退). At the age of 30, your body will stop producing the high levels of growth hormone it previously produces. Your body senses that it's done growing at 30, so it uses the resources elsewhere. Unfortunately, that means that your muscle will deteriorate more rapidly than before. While you can’t block age's effects or your metabolism, you can fight against it with regular exercise that builds muscle.Although muscle deteriorates quicker with age, a lack of exercise will hurt your metabolism at any age. The muscle developed during exercise is vital to maintaining a healthy body with a normal basal metabolic rate. Therefore, while cardiovascular(心血管的)exercise will burn fat during the work out, building muscle will wisely allow your body to use more calories to give you healthy energy instead of stored fat.Another large factor that determines your basal metabolic rate is your eating habits. Metabolism-Advice. com suggests eating small meals every two to three hours. This will make sure that your metabolism is constantly working throughout your day. Another large factor is how healthily you eat. Taking in the required calories for your amount of daily activity will help keep your metabolism from lowering, but taking in too many calories may lead to fat.Title: About slow metabolismI . Definitions●metabolis m—how quickly and efficiently your body creates the energy for itto function correctly●basal metabolic rat e—the amount of 71. by your body when you're resting●slow metabolism-slow basal metabolic rateII. 72. of slow metabolism●giving a person less energy●getting a person to 73._______________III. 74. of slow metabolism●deterioration of your body 75. exercise●unhealthy 76.●unhealthy dietIV. 77. to slow metabolism●78.____________________ to build muscle●eating more often but 79. ____________________●80._________________ your body requires for the daily activitiesSection B (10 marks)Directions: Read the following passage, and answer the questions according to the information given in the passage.Elephants and people are in competition for space. In much of Africa, elephants are now put in national parks. Elephants suffered a serious and steady decrease in number in the 1970s.This was the same time when scientists were beginning to learn a great deal about elephants and their behavior. Studies through the 1980s and into the 1990s showed a lot about their sounds and methods of communication.In Kenya alone, in the 1970s and 1980s, the elephant population decreased from 170,000 t0 25,000. The sharp drop in number was the result of poachers (偷猎者) illegally killing elephants for their ivory. The price of ivory went up from $ 3 a pound to $ 50 to $ 100 a pound. Africa became very attractive to poachers. Bull elephants carried larger tusks (象牙) , so they were more often killed. With males gone and older females killed by poachers as well, there were many young elephants unable to benefit from the wisdom of the older females and matriarchs, who lead the herds.Kenya took a stand that international trade in ivory was officially forbidden, and $ 3, 000,000 worth of confiscated (没收的) ivory was burned in Kenya. The following year, only 50 elephants were lost to poachers in Kenya instead of 3,000. But Kenya has the fastest growing human population in the world. People throughout Africa won’t tolerate elephants eating their crops and destroying their livelihoods. In South Africa, elephants live behind the fences of national parks. In some parts of Africa, big-game hunters pay a lot of money to hunt elephants. This keeps their numbers down, and the money goes toward conservation. In Kenya, there are some attempts at birth control to keep the elephant population in manageable numbers to reduce conflicts with people.Faced with a growing human population, elephants are losing the battle for space. It’s unlikely, though, that they will become extinct(绝种的). They will live in natural parks that bring tourists to Africa as well as India and other parts of Asia. The money from tourism will help elephants to survive.81. What’s the reason for elephant population decrease? ( No more than 8 words)82. Why were bull elephants at higher risk of being killed? (No more than 6 words)83. How can we reduce conflicts with elephants? (No more than 9 words)84.Why is it not likely that elephants will become extinct? (no more than 15 words)Section C (25 marks)Directions: Write an English composition according to the instructions given below in Chinese 请一下列词语为关键词写一篇英语短文。
湖南省岳阳县一中2015届高三年级第三次月考语文试卷
湖南省岳阳县一中2015届高三年级第三次月考试卷语文时量:150分钟总分:150分命题人:徐新农审题人:易霞霞一、语言文字运用(12分,每小题3分)1.下列词语中加点字的读音,全都正确....的一组是()A.裨.益bì盘桓.huán偌.大nuî潜.移默化qiánB.昭.示zhāo挫.折cuî刹.那shà既往不咎.jiùC.教诲.huì粘.贴zhān 着.陆zhuï徇.私舞弊xùnD.造诣.yì即.便jí溯.源sh uî胜券.在握quàn2.下列各句中,没有...的一项是()..错别字A.帐篷寒暄唇枪舌箭弊绝风清B.遐想拇指真知灼见雍容华贵C.匮乏城阕短小精悍相形见绌D. 文采戍边凭心而论声名鹊起3.依次在下列横线处填入词语,最恰当...的一项是()(1)现代自然科学是研究单个的事物,还要研究事物、现象的变化发展过程,研究事物之间的各种关系,这就使自然科学发展成为严密的综合体系。
(2)中国古代文化是一座巍峨的高峰,不管我们在儒、释、道哪一条路上行走,,最终都必然会在山顶上相逢。
(3)从此以后,黑格尔将父亲的话牢记在心,每当要出现、贬低别人、粗暴打断别人说话苗头的时候,他都会想起父亲的提醒:“马车越空,噪音就越大”。
A.不止异曲同工自以为是B.不只异曲同工自行其是C.不止殊途同归自行其是D.不只殊途同归自以为是4.下列各句中,没有语病....的一句是()A.车辆如万一在高速公路上发生事故,交通部门要及时在规定位置设置警告标志,以防止二次事故的发生。
B.纵观世界各国的企业发展史,你就会发现,一个企业能否获得成功,往往不取决于它的规模和历史,而取决于它的经营理念。
C.这次招聘,一半以上的应聘者曾多年担任外资企业的中高层管理岗位,有较丰富的管理经验。
D.教育主管部门要求,各级各类学校学生的生活用品以及床上用品都应由学生自主选购,不得统一配备。
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湖南省岳阳县一中2015届高三10月第二次月考数 学(文科)一、选择题(下列各小题的四个答案中仅有一个是正确的,请将正确答案填入答题纸的表格中,每小题5分,50分)1.已知全集{}0,1,2,3,4U =,集合{}{}1,2,3,2,4A B ==,则()U A B ð为 ( ) A.{}1,2,4 B.{}2,3,4 C. {}0,2,3,4 D. {}0,2,42. 函数()sin(2)3f x x π=+的一个对称中心是 ( )A.(,0)3πB. (,0)12πC. (,0)6πD. (,0)12π-3.将函数y =sin x 的图象上所有的点向右平行移动π10个单位长度,再把所得各点的横坐标伸长到原来的2倍(纵坐标不变),所得图象的函数解析式是 ( )A . y =sin(2x -π10)B .y =sin(2x -π5)C .y =sin(12x -π10)D .y =sin(12x -π20)4.设函数f (x )=⎩⎪⎨⎪⎧⎝⎛⎭⎫12x -7,x <0,x ,x ≥0,若f (a )<1,则实数a 的取值范围是 ( ) A .(-∞,-3) B .(1,+∞)C .(-3,1)D .(-∞,-3)∪(1,+∞)5.函数()log 1(01)a f x x a =+<<的图像大致为 ( )6.以下有关命题的说法错误的是( ) A .命题“若2320x x -+=则x =1”的逆否命题为“若21,320x x x ≠-+≠则” B .“1x =”是“2320x x -+=”的充分不必要条件C .若p q ∧为假命题,则p 、q 均为假命题A.B.C.D.D .对于命题22:10,:,10p x R x x p x R x x ∃∈++<⌝∀∈++≥使得则均有7. 已知一元二次函数2()f x x bx c =++,且不等式20x bx c ++>的解集为{}1|<-1>2x x x 或,则(10)>0x f 的解集为 ( )A .{}|<-1>lg2x x x 或 B .{}|-1<<lg2x x C .{}|>-lg2x x D . {}|<-lg2x x8.若函数f (x )=2x 2-ln x 在其定义域内的一个子区间(k -1,k +1)内至少有一个极值点,则实数k 的取值范围是 ( ) A .[1,+∞) B .[1,32) C .[1,2) [32,2)9.锐角ABC ∆中,,,a b c 分别是三内角,,A B C 的对边,且2B A =,则ba的取值范围是( ) A .(2,2)-B .(0,2)C.2)D.10.定义在(0,)+∞上的函数()f x 满足条件(2)2()f x f x =,且当(1,2]x ∈时,()2f x x =-,若12,x x 是方程() (01)f x a a =<≤的两个实根,则12x x -不可能是( ) A .30 B .56 C .80 D .112二.填空题:(共35分把答案填在答题纸相应题号后的横线上) 11.函数ln (0)y x x =->的单调增区间为________________.12.已知函数()ln(1)f x x =++的定义域为M ,则M=13.命题p:x R ∃∈,使2(1)10x a x +++<,若p ⌝为假命题,则实数a 的取值范围是14.函数sin()(0,0,||)2y A x A πωϕωϕ=+>><的部分图象如图所示,则函数的解析式为15.对于三次函数d cx bx ax x f +++=23)()0(≠a ,给出定义:)(x f /是函数)(x f 的导函数,)(//x f 是)(x f /的导函数,若方程0)(//=x f 有实数解0x ,则称点))(,(00x f x 为函数)(x f y =的“拐点”。
某同学经研究发现:任何一个三次函数都有“拐点”;任何一个三次函数都有对称中心,且拐点就是对称中心。
若12532131)(23-+-=x x x x f ,请你根据这一发现,求:(1)函数12532131)(23-+-=x x x x f 的对称中心为__________; (2)122015()()()201620162016f f f +++ =________三、解答题(6小题共75分,写出必要的文字说明或理由)16.(本题满分12分)已知△ABC 的内角C B A ,,所对的边分别为,,,c b a 且53cos ,2==B a . (1) 若4=b , 求sin B ,A sin 的值;(2) 若△ABC 的面积,4=∆ABC S 求c b ,的值.17.(本题满分12分)设函数f (x )=ax n (1-x )+b (x >0),n 为正整数,a ,b 为常数.曲线y =f (x )在(1,f (1))处的切线方程为x +y =1. (1) 求a ,b 的值; (2) 求函数f (x )的最大值.18.(本题满分12分) 已知函数()coscos )222x x x f x =+. (1)求函数f(x)的最小正周期及单调递增区间; (2)若f(x)=1,求2cos(2)3x π-的值.19.(本题满分13分)已知集合{|015}A x R ax =∈<+≤, 1{|2}2B x R x =∈-<≤ (1)B A ,能否相等?若能,求出实数a 的值,若不能,试说明理由?(2)若命题,:A x p ∈命题B x q ∈:且p 是q 的充分不必要条件,求实数a 的取值范围;20.(本题满分13分)已知定义域为R 的函数f (x )=-2x +b2x +1+a 是奇函数.(1)求a ,b 的值;(2)证明:函数f (x )在R 上是减函数;(3)若对任意的t ∈R ,不等式f (t 2-2t )+f (2t 2-k )<0恒成立,求k 的取值范围.21.(本题满分13分)已知函数()(ln )f x x a x =+有极小值2e --. (1)求实数a 的值; (2)若Z k ∈,且1)(-<x x f k 对任意1>x 恒成立,求k 的最大值; (3)当1,(,)n m n m Z >>∈时,证明:()()nm mn nm mn >.岳阳县一中2015届高三第二次月考试题文科数学参考答案1.已知全集{}0,1,2,3,4U =,集合{}{}1,2,3,2,4A B ==,则()U A B ð为( D ) A.{}1,2,4 B.{}2,3,4 C. {}0,2,3,4 D. {}0,2,42. 函数()sin(2)3f x x π=+的一个对称中心是 ( A )A.(,0)3πB. (,0)12πC. (,0)6πD. (,0)12π-3.将函数y =sin x 的图象上所有的点向右平行移动π10个单位长度,再把所得各点的横坐标伸长到原来的2倍(纵坐标不变),所得图象的函数解析式是 (C )A .y =sin(2x -π10)B .y =sin(2x -π5)C .y =sin(12x -π10)D .y =sin(12x -π20)4.设函数f (x )=⎩⎪⎨⎪⎧⎝⎛⎭⎫12x -7,x <0,x ,x ≥0,若f (a )<1,则实数a 的取值范围是( C ) A .(-∞,-3) B .(1,+∞)C .(-3,1)D .(-∞,-3)∪(1,+∞) 5.函数()log 1(01)a f x x a =+<<的图像大致为( A )6.以下有关命题的说法错误的是( C ) A .命题“若02x 3x 2=+-则x=1”的逆否命题为“若02x 3x ,1x 2≠+-≠则” B .“1x =”是“”02x 3x 2=+-的充分不必要条件 C .若q p ∧为假命题,则p 、q 均为假命题D .对于命题01x x ,R x :p ,01x x R x :p 22≥++∈∀⌝<++∈∃均有则使得7.已知一元二次函数2()f x x bx c =++,且不等式20x bx c ++>的解集为{}1|<-1>2x x x 或,则(10)>0x f 的解集为( C )A .{}|<-1>lg2x x x 或B .{}|-1<<lg2x xC .{}|>-lg2x x D .{}|<-lg2x x8. 若函数f (x )=2x 2-ln x 在其定义域内的一个子区间(k -1,k +1)内至少有一个极值点,则实数k 的取值范围是 ( B ) A .[1,+∞) B .[1,32) C .[1,2)D .[32,2)9.锐角ABC ∆中,,,a b c 分别是三内角,,A B C 的对边,且2B A =,则ba的取值范围是(D )A .(2,2)-B .(0,2)C .2)D .10.定义在(0,)+∞上的函数()f x 满足条件(2)2()f x f x =,且当(1,2]x ∈时,()2f x x =-,若12,x x 是方程() (01)f x a a =<≤的两个实根,则12x x -不可能是(C ) A .30 B .56 C .80 D .11211.函数ln (0)y x x =->的单调增区间为________________.[4,)+∞((4,)+∞也对)12. 已知函数()ln(1)f x x =++的定义域为M ,则M={|11}x x -<<13.命题p:x R ∃∈,使2(1)10x a x +++<,若p ⌝为假命题,则实数a 的取值范围 是 (,3)(1,)-∞-+∞14.函数sin()(0,0,||)2y A x A πωϕωϕ=+>><的部分图象如图所示,则函数的解析式为2sin(2)3y x π=-15.对于三次函数d cx bx ax x f +++=23)()0(≠a ,给出定义:)(x f /是函数)(x f 的导函数,)(//x f 是)(x f /的导函数,若方程0)(//=x f 有实数解0x ,则称点))(,(00x f x 为函数)(x f y =的“拐点”。
某同学经研究发现:任何一个三次函数都有“拐点”;任何一个三次函数都有对称中心,且拐点就是对称中心。
若12532131)(23-+-=x x x x f ,请你根据这一发现, 求:(1)函数12532131)(23-+-=x x x x f 的对称中心为__________;(2)122015()()()201620162016f f f +++ =________ (1)(12 ,1)(2)201516.(本题满分12分)已知△ABC 的内角C B A ,,所对的边分别为,,,c b a 且53cos ,2==B a . (1) 若4=b , 求sin B ,A sin 的值;(2) 若△ABC 的面积,4=∆ABC S 求c b ,的值. 解: (1)∵053cos >=B , 且π<<B 0, ∴ 54cos 1sin 2=-=B B . ……2分由正弦定理得BbA a sin sin =, …… 3分 ∴524542sin sin =⨯==b B a A . ………… 6分 (2)∵,4sin 21==∆B ac S ABC ∴454221=⨯⨯⨯c .…… 9分∴ 5=c . ……10分 由余弦定理得B ac c a b cos 2222-+=,…… 11分∴ 175352252cos 22222=⨯⨯⨯-+=-+=B ac c a b . ……12分17.设函数f (x )=ax n (1-x )+b (x >0),n 为正整数,a ,b 为常数.曲线y =f (x )在(1,f (1))处的切线方程为x +y =1. (1)求a ,b 的值; (2)求函数f (x )的最大值. 解:(1)因为f (1)=b ,由点(1,b )在x +y =1上,可得1+b =1,即b =0.因为f ′(x )=anx n -1-a (n +1)x n ,所以f ′(1)=-a .又因为切线x +y =1的斜率为-1, 所以-a =-1,即a =1.故a =1,b =0. (2)由(1)知,f (x )=x n (1-x )=x n -x n +1,f ′(x )=(n +1)x n -1⎝⎛⎭⎫n n +1-x . 令f ′(x )=0,解得x =n n +1,即f ′(x )在(0,+∞)上有唯一零点x 0=nn +1.在⎝⎛⎭⎫0,nn +1上,f ′(x )>0,故f (x )单调递增;而在⎝⎛⎭⎫nn +1,+∞上,f ′(x )<0,f ′(x )单调递减.故f (x )在(0,+∞)上的最大值为f ⎝⎛⎭⎫n n +1=⎝⎛⎭⎫n n +1n ⎝⎛⎭⎫1-n n +1=nn(n +1) n +1.18.本题满分12分)已知函数()coscos )222x x xf x =+. (1)求函数f(x)的最小正周期及单调递增区间; (2)若f(x)=1,求2cos(2)3x π-的值.解:(1)11()coscos )(1cos )sin().222262x x x f x x x x π=+=++=++所以函数f(x)的最小正周期为T =2π. 4分 令22,262k x k k πππππ-≤+≤+∈Z ,得222,33k x k k ππππ-≤≤+∈Z 函数y =f(x)的单调递增区间为2[2,2],()33k k k ππππ-+∈Z . 6分 (2)11()sin()1,sin()6262f x x x ππ=++=+=即,2221cos(2)cos 2()2cos ()12sin ()133362x x x x ππππ-=-=--=+-=- 12分 19.(本题满分13分)已知集合{|015}A x R ax =∈<+≤, 1{|2}2B x R x =∈-<≤ (1)B A ,能否相等?若能,求出实数a 的值,若不能,试说明理由?(2)若命题,:A x p ∈命题B x q ∈:且p 是q 的充分不必要条件,求实数a 的取值范围;(1)当0a >时14A x x a a ⎧⎫=-<≤⎨⎬⎩⎭112242a a a ⎧-=-⎪⎪∴⇒=⎨⎪=⎪⎩当0<a 时⎭⎬⎫⎩⎨⎧-<≤=a x axA 14显然B A ≠故B A =时,2=a (2)B A q p ≠⊂⇒⇒41510≤<-⇒≤+<ax ax当0>a 时, ⎭⎬⎫⎩⎨⎧≤<-=a x a x A 41则⎪⎩⎪⎨⎧≤->-⎪⎩⎪⎨⎧<-≥-2421124211a a a a 或解得2>a 当0<a 时,⎭⎬⎫⎩⎨⎧-<≤=a x ax A 14则821214-<⇒⎪⎩⎪⎨⎧≤-->a aa综上p 是q 的充分不必要条件,实数a 的取值范围是,2>a 或8-<a 20.(13分)已知定义域为R 的函数f (x )=-2x +b2x +1+a 是奇函数.(1)求a ,b 的值;(2)证明:函数f (x )在R 上是减函数;(3)若对任意的t ∈R ,不等式f (t 2-2t )+f (2t 2-k )<0恒成立,求k 的取值范围.(1)解 因为f (x )是R 上的奇函数,故f (0)=0,即-1+b 2+a =0,解得b =1, 从而有f (x )=-2x +12x 1+a .又由f (1)=-f (-1)知-2+14+a =--12+11+a,解得a =2.∴f (x )=12⎝ ⎛⎭⎪⎫1-2x2x +1. ∴a =2,b =1. 4分(2)证明 设x 1<x 2, f (x 1)-f (x 2)=1-2x 12(2x 1+1)-1-2x 22(2x 2+1) =(1-2x 1)(1+2x 2)-(1-2x 2)(1+2x 1)2(2x 1+1)(2x 2+1)=2x 2-2x 1(2x 1+1)(2x 2+1).∵x 1<x 2,则2x 2-2x 1>0,∴f (x 1)>f (x 2). 故f (x )是R 上的减函数. 4分(3)解 由(2)知f (x )在R 上为减函数,又因为f (x )是奇函数,从而不等式f (t 2-2t )+f (2t 2-k )<0等价于f (t 2-2t )<-f (2t 2-k )=f (-2t 2+k ).因为f (x )是R 上的减函数,由上式推得t 2-2t >-2t 2+k . 即对一切t ∈R 有3t 2-2t -k >0恒成立, 从而Δ=4+12k <0,解得k <-13. 4分21.已知函数()(ln )f x x a x =+有极小值2e --. (1)求实数a 的值; (2)若Z k ∈,且1)(-<x x f k 对任意1>x 恒成立,求k 的最大值; (3)当1,(,)n m n m Z >>∈时,证明:()()nm mn nm mn >.解析(Ⅰ)()1ln f x a x '=++,令1()0a f x x e --'>⇒>,令1()00a f x x e --'<⇒<<故()f x 的极小值为112()a a f e e e -----=-=-,得1a =. 4分(Ⅱ)当1x >时,令()ln ()11f x x x xg x x x +==--,∴()'22ln ()1x x g x x --=- 令()2ln h x x x =--,∴'11()10x h x x x-=-=>,故()y h x =在(1,)+∞上是增函数 由于(3)1ln30,(4)2ln 40h h =-<=->,∴ 存在()03,4x ∈,使得0()0h x =. 则()01,,()0x x h x ∈<,知()g x 为减函数;()'0,,()0x x h x ∈+∞>,知()g x 为增函数.∴ 000min 000ln ()()1x x x g x g x x x +===-∴ 0,k x <又()03,4x ∈ ,k Z ∈,所以max k =3. 9分(Ⅲ)要证()()mnn m mn nm >即证ln ln ln ln m m nm n n n nm m +>+即证ln ln 11n n m m n m >--,令ln ()1x xx x ϕ=-,得()21ln ()1x x x x ϕ--'=-令1()1ln ,'()10,(1)()g x x x g x x g x x=--=->>∴ 为增函数,又(1)0,()1ln 0g g x x x ==--> ,所以'()0x ϕ>∴ ()y x ϕ=是增函数,又 1n m >>=∴ ()()nm m n nm mn >. 13分。