2018届上海市建平中学高三上学期期中考试数学试题(3)
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2018-2019学年上海市浦东新区建平中学高三(上)期中数学试卷一.填空题1.(3分)设函数,则f(f(2))=2.(3分)在各项为实数的等比数列{a n}中,a5+8a2=0,则公比q的值为3.(3分)若,,,,则tanα= 4.(3分)设集合A={x|x2﹣2x≥0},B={x|2x﹣1≤1},则(∁R A)∩B=5.(3分)某校邀请5位同学的父母共10人中的4位来学校介绍经验,如果这4位来自4个不同的家庭,那么不同的邀请方案的种数是6.(3分)从原点O向圆x2+y2﹣12y+27=0作两条切线,则该圆夹在两条切线间的劣弧长为.7.(3分)已知数列{a n}的前n项和S n满足:对于任意m,n∈N*,都有S n+S m=S n+2mn,若a1=1,则a2018=+m8.(3分)已知函数f(x)的定义域为R,当x<0时,f(x)=x3﹣1;当﹣1≤x≤1时,f(﹣x)=﹣f(x);当x>时,f(x+)=f(x﹣),则f(6)=.9.(3分)已知f(x)是定义在R上的偶函数,且在区间(﹣∞,0]上单调递增,若实数a满足f(log2|a﹣1|)>f(﹣2),则a的取值范围是10.(3分)在锐角三角形ABC中,A、B、C的对边分别为a、b、c,a2+b2=6abcosC,则=11.(3分)已知关于x的一元二次不等式ax2+2x+b>0的解集为{x|x≠c},则(其中a+c≠0)的取值范围为.12.(3分)若定义域均为D的三个函数f(x),g(x),h(x)满足条件:对任意x∈D,点(x,g(x)与点(x,h(x)都关于点(x,f(x)对称,则称h(x)是g(x)关于f(x)的“对称函数”.已知g(x)=,f(x)=2x+b,h(x)是g(x)关于f(x)的“对称函数”,且h(x)≥g(x)恒成立,则实数b的取值范围是.二.选择题13.(3分)已知实数x,y满足a x<a y(0<a<1),则下列关系式恒成立的是()A.B.ln(x2+1)>ln(y2+1)C.sinx>siny D.x3>y314.(3分)已知点A(﹣2,0)、B(3,0),动点P(x,y)满足,则点P的轨迹是()A.圆B.椭圆C.双曲线D.抛物线15.(3分)已知数列{a n}是公比为q(q≠1)的等比数列,则数列:①{2an};②{a n2};③;④{a n a n+1};⑤{a n+a n+1};等比数列的个数为()A.2B.3C.4D.516.(3分)设函数f1(x)=x2,f2(x)=2(x﹣x2),,,i=0,1,2,…,99.记I k=|f k(a1)﹣f k(a0)|+|f k(a2)﹣f k(a1)丨+…+|f k (a99)﹣f k(a98)|,k=1,2,3,则()A.I1<I2<I3B.I2<I1<I3C.I1<I3<I2D.I3<I2<I1三.解答题17.如图,在四棱锥P﹣ABCD中,底面ABCD为直角梯形,BC∥AD,AB⊥BC,∠ADC=45°,PA⊥平面ABCD,AB=AP=1,AD=3.(1)求异面直线PB与CD所成角的大小;(2)求点D到平面PBC的距离.18.设函数f(x)=sin(ωx﹣)+sin(ωx﹣),其中0<ω<3,已知f()=0.(Ⅰ)求ω;(Ⅱ)将函数y=f(x)的图象上各点的横坐标伸长为原来的2倍(纵坐标不变),再将得到的图象向左平移个单位,得到函数y=g(x)的图象,求g(x)在[﹣,]上的最小值.19.某沿海城市的海边有两条相互垂直的直线型公路l1、l2,海岸边界MPN近似地看成一条曲线段.为开发旅游资源,需修建一条连接两条公路的直线型观光大道AB,且直线AB与曲线MPN有且仅有一个公共点P(即直线与曲线相切),如图所示.若曲线段MPN是函数图象的一段,点M到l1、l2的距离分别为8千米和1千米,点N到l2的距离为10千米,以l1、l2分别为x、y 轴建立如图所示的平面直角坐标系xOy,设点P的横坐标为p.(1)求曲线段MPN的函数关系式,并指出其定义域;(2)若某人从点O沿公路至点P观景,要使得沿折线OAP比沿折线OBP的路程更近,求p的取值范围.20.对于函数,定义f1(x)=f(x),f n(x)=f[f n(x)](n∈N*),+1已知偶函数g(x)的定义域为(﹣∞,0)∪(0,+∞),g(1)=0,当x>0且x≠1时,g(x)=f2018(x).(1)求f2(x),f3(x),f4(x),f2018(x);(2)求出函数y=g(x)的解析式;(3)若存在实数a、b(a<b),使得函数g(x)在[a,b]上的值域为[mb,ma],求实数m的取值范围.21.对于无穷数列{a n},记T={x|x=a j﹣a i,i<j},若数列{a n}满足:“存在t∈T,使得只要a m﹣a k=t(m,k∈N*,m>k),必有a m+1﹣a k+1=t”,则称数列具有性质P(t).(1)若数列{a n}满足,判断数列{a n}是否具有性质P(2)?是否具有性质P(4)?说明理由;(2)求证:“T是有限集”是“数列{a n}具有性质P(0)”的必要不充分条件;(3)已知{b n}是各项均为正整数的数列,且{b n}既具有性质P(2),又具有性质P(5),求证:存在正整数N,使得a N,a N+1,a N+2,…,a N+K,…是等差数列.2018-2019学年上海市浦东新区建平中学高三(上)期中数学试卷参考答案与试题解析一.填空题1.(3分)设函数,则f(f(2))=﹣1【分析】推导出f(2)=π(4﹣5)=﹣π,从而f(f(2))=f(﹣π)=cos(﹣π)=cosπ,由此能求出结果.【解答】解:∵函数,∴f(2)=π(4﹣5)=﹣π,f(f(2))=f(﹣π)=cos(﹣π)=cosπ=﹣1.故答案为:﹣1.2.(3分)在各项为实数的等比数列{a n}中,a5+8a2=0,则公比q的值为﹣2【分析】由等比数列的性质知q3=﹣8,从而解得.【解答】解:∵a5+8a2=0,∴a2q3+8a2=0,即q3=﹣8,解得q=﹣2.故答案为:﹣2.3.(3分)若,,,,则tanα= 7【分析】利用向量的数量积和三角函数同角公式可得.【解答】解:因为•=(1,2)•(cosα,sinα)=cosα+2sinα,3•=3(﹣2,1)•(cosα,sinα)=﹣6cosα+3sinα,∴cosα+2sinα=﹣6cosα+3sinα,∴sinα=7cosα,tanα=7,故答案为:7.4.(3分)设集合A={x|x2﹣2x≥0},B={x|2x﹣1≤1},则(∁R A)∩B=(0,1] 【分析】化简集合A、B,根据补集与交集的定义计算即可.【解答】解:集合A={x|x2﹣2x≥0}={x|x≤0或x≥2},集合B={x|2x﹣1≤1}={x|x﹣1≤0}={x|x≤1},∴∁R A={x|0<x<2},∴(∁R A)∩B={x|0<x≤1}=(0,1].故答案为:(0,1].5.(3分)某校邀请5位同学的父母共10人中的4位来学校介绍经验,如果这4位来自4个不同的家庭,那么不同的邀请方案的种数是80【分析】用分步计数原理:①从5个家庭中选4个家庭;②从每个家庭中选出1个.然后相乘可得.【解答】解:分步进行:第一步:从5个家庭中选出4个家庭,有C=5种;第二步:从选出的4个家庭的每个家庭的父母亲中选出1位来,有C×C×C×C=16;根据分步计数原理得:不同的邀请方案的种数数:5×16=80.故答案为:80.6.(3分)从原点O向圆x2+y2﹣12y+27=0作两条切线,则该圆夹在两条切线间的劣弧长为2π.【分析】把圆的方程化为标准方程后,找出圆心C的坐标和圆的半径r,根据AC 与BC为圆的半径等于3,OC的长度等于6,利用直角三角形中一直角边等于斜边的一半得到角AOB等于2×30°,然后根据四边形的内角和定理求出角BCA 的度数,然后由角BCA的度数和圆的半径,利用弧长公式即可求出该圆夹在两条切线间的劣弧长.【解答】解:把圆的方程化为标准方程为:x2+(y﹣6)2=9,得到圆心C的坐标为(0,6),圆的半径r=3,由圆切线的性质可知,∠CBO=∠CAO=90°,且AC=BC=3,OC=6,则∠AOB=∠BOC+∠AOC=60°,所以∠ACB=120°,所以该圆夹在两条切线间的劣弧长l==2π.故答案为:2π7.(3分)已知数列{a n}的前n项和S n满足:对于任意m,n∈N*,都有S n+S m=S n+m+2mn,若a1=1,则a2018=﹣4033【分析】根据题意,在S n+S m=S n+m+2mn中,用特殊值法分析:令m=1可得:S n+S1=S n+1+2n,变形可得S n+1﹣S n=1﹣2n,再令n=2018计算可得答案.【解答】解:根据题意,在S n+S m=S n+m+2mn中,令m=1可得:S n+S1=S n+1+2n,又由a1=1,即S1=a1=1,则有S n+1=S n+1+2n,变形可得:S n+1﹣S n=1﹣2n,则a2018=S2018﹣S2017=1﹣2×2017=﹣4033;故答案为:﹣4033.8.(3分)已知函数f(x)的定义域为R,当x<0时,f(x)=x3﹣1;当﹣1≤x≤1时,f(﹣x)=﹣f(x);当x>时,f(x+)=f(x﹣),则f(6)= 2.【分析】求得函数的周期为1,再利用当﹣1≤x≤1时,f(﹣x)=﹣f(x),得到f(1)=﹣f(﹣1),当x<0时,f(x)=x3﹣1,得到f(﹣1)=﹣2,即可得出结论.【解答】解:∵当x>时,f(x+)=f(x﹣),∴当x>时,f(x+1)=f(x),即周期为1.∴f(6)=f(1),∵当﹣1≤x≤1时,f(﹣x)=﹣f(x),∴f(1)=﹣f(﹣1),∵当x<0时,f(x)=x3﹣1,∴f(﹣1)=﹣2,∴f(1)=﹣f(﹣1)=2,∴f(6)=2;故答案为:29.(3分)已知f(x)是定义在R上的偶函数,且在区间(﹣∞,0]上单调递增,若实数a满足f(log2|a﹣1|)>f(﹣2),则a的取值范围是(3,)∪(,5)【分析】根据题意,分析可得f(x)在[0,+∞)上为减函数,结合函数的奇偶性分析可得f(log2|a﹣1|)>f(﹣2)可以转化为﹣2<log2|a﹣1|<2,解可得a的取值范围,即可得答案.【解答】解:根据题意,f(x)是定义在R上的偶函数,且在区间(﹣∞,0]上单调递增,则f(x)在[0,+∞)上为减函数,则f(log2|a﹣1|)>f(﹣2)⇒f(|log2|a﹣1||)>f(2)⇒|log2|a﹣1||<2⇒﹣2<log2|a﹣1|<2,变形可得:<|a﹣1|<4,解可得:﹣3<a<或<x<5;即不等式的解集为(﹣3,)∪(,5);故答案为:(﹣3,)∪(,5).10.(3分)在锐角三角形ABC中,A、B、C的对边分别为a、b、c,a2+b2=6abcosC,则=4【分析】由题意利用余弦定理可得c2=(a2+b2),再利用行列式的运算、同角三角函数的基本关系,求得要求式子的值.【解答】解:在锐角三角形ABC中,∵a2+b2=6abcosC=6ab•,∴c2=(a2+b2).则=+=tanC(+)=•(+)=•====4,故答案为:4.11.(3分)已知关于x的一元二次不等式ax2+2x+b>0的解集为{x|x≠c},则(其中a+c≠0)的取值范围为(﹣∞,﹣6]∪[6,+∞).【分析】由条件利用二次函数的性质可得ac=﹣1,ab=1,再根据则=(a﹣b)+,利用基本不等式求得它的范围.【解答】解:根据关于x的一元二次不等式ax2+2x+b>0的解集为{x|x≠c},可得a>0,对应的二次函数的图象的对称轴为x=﹣=c,△=4﹣4ab=0,∴ac=﹣1,ab=1,∴c=﹣,b=.则==(a﹣b)+,当a﹣b>0时,由基本不等式求得(a﹣b)+≥6,当a﹣b<0时,由基本不等式求得﹣(a﹣b)﹣≥6,即(a﹣b)+≤﹣6故(其中a+c≠0)的取值范围为:(﹣∞,﹣6]∪[6,+∞),故答案为:(﹣∞,﹣6]∪[6,+∞).12.(3分)若定义域均为D的三个函数f(x),g(x),h(x)满足条件:对任意x∈D,点(x,g(x)与点(x,h(x)都关于点(x,f(x)对称,则称h(x)是g(x)关于f(x)的“对称函数”.已知g(x)=,f(x)=2x+b,h(x)是g(x)关于f(x)的“对称函数”,且h(x)≥g(x)恒成立,则实数b的取值范围是[,+∞).【分析】根据对称函数的定义,结合h(x)≥g(x)恒成立,转化为点到直线的距离d≥1,利用点到直线的距离公式进行求解即可.【解答】解:解:∵x∈D,点(x,g(x))与点(x,h(x))都关于点(x,f(x))对称,∴g(x)+h(x)=2f(x),∵h(x)≥g(x)恒成立,∴2f(x)=g(x)+h(x)≥g(x)+g(x)=2g(x),即f(x)≥g(x)恒成立,作出g(x)和f(x)的图象,若h(x)≥g(x)恒成立,则h(x)在直线f(x)的上方,即g(x)在直线f(x)的下方,则直线f(x)的截距b>0,且原点到直线y=2x+b的距离d≥1,d=⇒b≥或b(舍去)即实数b的取值范围是[,+∞),二.选择题13.(3分)已知实数x,y满足a x<a y(0<a<1),则下列关系式恒成立的是()A.B.ln(x2+1)>ln(y2+1)C.sinx>siny D.x3>y3【分析】实数x,y满足a x<a y(0<a<1),可得x>y,对于A.B.C分别举反例即可否定,对于D:由于y=x3在R上单调递增,即可判断出正误.【解答】解:∵实数x,y满足a x<a y(0<a<1),∴x>y,A.取x=2,y=﹣1,不成立;B.取x=0,y=﹣1,不成立C.取x=π,y=﹣π,不成立;D.由于y=x3在R上单调递增,因此正确故选:D.14.(3分)已知点A(﹣2,0)、B(3,0),动点P(x,y)满足,则点P的轨迹是()A.圆B.椭圆C.双曲线D.抛物线【分析】由题意知(﹣2﹣x,y)•(3﹣x,y)=x2,化简可得点P的轨迹.【解答】解:∵动点P(x,y)满足,∴(﹣2﹣x,﹣y)•(3﹣x,﹣y)=x2,∴(﹣2﹣x)(3﹣x)+y2=x2,解得y2=x+6.∴点P的轨迹方程是抛物线.故选:D.15.(3分)已知数列{a n}是公比为q(q≠1)的等比数列,则数列:①{2an};②{a n2};③;④{a n a n+1};⑤{a n+a n+1};等比数列的个数为()A.2B.3C.4D.5【分析】利用等比数列的定义通项公式即可得出.【解答】解:数列{a n}是公比为q(q≠1)的等比数列,则①=,不是等比数列;②=q2;③是公比为的等比数列;④{a n a n+1}是公比为q2的等比数列;}不一定是等比数列,例如(﹣1)n.⑤{a n+a n+1综上:等比数列的个数为3.故选:B.16.(3分)设函数f1(x)=x2,f2(x)=2(x﹣x2),,,i=0,1,2,…,99.记I k=|f k(a1)﹣f k(a0)|+|f k(a2)﹣f k(a1)丨+…+|f k (a99)﹣f k(a98)|,k=1,2,3,则()A.I1<I2<I3B.I2<I1<I3C.I1<I3<I2D.I3<I2<I1【分析】根据记I k=|f k(a1)﹣f k(a0)|+|f k(a2)﹣f k(a1)丨+…+|f k(a99)﹣f k (a98)|,分别求出I1,I2,I3与1的关系,继而得到答案【解答】解:由,故==1,由,故×=×<1,+=,故I2<I1<I3,故选:B.三.解答题17.如图,在四棱锥P﹣ABCD中,底面ABCD为直角梯形,BC∥AD,AB⊥BC,∠ADC=45°,PA⊥平面ABCD,AB=AP=1,AD=3.(1)求异面直线PB与CD所成角的大小;(2)求点D 到平面PBC 的距离.【分析】(1)以A 为原点,AB 为x 轴,AD 为y 轴,AP 为z 轴,建立空间直角坐标系,利用向量法能求出异面直线PB 与CD 所成角大小.(2)求出平面PBC 的一个法向量,利用向量法能求出点D 到平面PBC 的距离. 【解答】解:(1)以A 为原点,AB 为x 轴,AD 为y 轴,AP 为z 轴,建立如图所示空间直角坐标系,则P (0,0,1),B (1,0,0),C (1,2,0)D (0,3,0),∴=(1,0,﹣1),=(﹣1,1,0),……(3分)设异面直线PB 与CD 所成角为θ,则cosθ==,……(6分)所以异面直线PB 与CD 所成角大小为.……(7分)(2)设平面PBC 的一个法向量为=(x ,y ,z ),=(1,0,﹣1),=(0,2,0),=(﹣1,1,0),则,取x=1,得=(1,0,1),……(4分)∴点D 到平面PBC 的距离d==.……(7分)18.设函数f (x )=sin (ωx ﹣)+sin (ωx ﹣),其中0<ω<3,已知f ()=0.(Ⅰ)求ω;(Ⅱ)将函数y=f(x)的图象上各点的横坐标伸长为原来的2倍(纵坐标不变),再将得到的图象向左平移个单位,得到函数y=g(x)的图象,求g(x)在[﹣,]上的最小值.【分析】(Ⅰ)利用三角恒等变换化函数f(x)为正弦型函数,根据f()=0求出ω的值;(Ⅱ)写出f(x)解析式,利用平移法则写出g(x)的解析式,求出x∈[﹣,]时g(x)的最小值.【解答】解:(Ⅰ)函数f(x)=sin(ωx﹣)+sin(ωx﹣)=sinωxcos﹣cosωxsin﹣sin(﹣ωx)=sinωx﹣cosωx=sin(ωx﹣),又f()=sin(ω﹣)=0,∴ω﹣=kπ,k∈Z,解得ω=6k+2,又0<ω<3,∴ω=2;(Ⅱ)由(Ⅰ)知,f(x)=sin(2x﹣),将函数y=f(x)的图象上各点的横坐标伸长为原来的2倍(纵坐标不变),得到函数y=sin(x﹣)的图象;再将得到的图象向左平移个单位,得到y=sin(x+﹣)的图象,∴函数y=g(x)=sin(x﹣);当x∈[﹣,]时,x﹣∈[﹣,],∴sin(x﹣)∈[﹣,1],∴当x=﹣时,g(x)取得最小值是﹣×=﹣.19.某沿海城市的海边有两条相互垂直的直线型公路l1、l2,海岸边界MPN近似地看成一条曲线段.为开发旅游资源,需修建一条连接两条公路的直线型观光大道AB,且直线AB与曲线MPN有且仅有一个公共点P(即直线与曲线相切),如图所示.若曲线段MPN是函数图象的一段,点M到l1、l2的距离分别为8千米和1千米,点N到l2的距离为10千米,以l1、l2分别为x、y 轴建立如图所示的平面直角坐标系xOy,设点P的横坐标为p.(1)求曲线段MPN的函数关系式,并指出其定义域;(2)若某人从点O沿公路至点P观景,要使得沿折线OAP比沿折线OBP的路程更近,求p的取值范围.【分析】(1)由题意得M(1,8),则a=8,故曲线段MPN的函数关系式为,可得其定义域;(2),设与联立求出A,B的坐标,即可求出最短长度p的取值范围.【解答】解:(1)由题意得M(1,8),则a=8,故曲线段MPN的函数关系式为,(4分)又得,所以定义域为[1,10].…(6分)(2),设由得kpx2+(8﹣kp2)x﹣8p=0,△=(8﹣kp2)2+32kp2=(kp2+8)2=0,…(8分)∴kp2+8=0,∴,得直线AB方程为,…(10分)得,故点P为AB线段的中点,由即p2﹣8>0…(12分)得时,OA<OB,所以,当时,经点A至P路程最近.(14分)20.对于函数,定义f1(x)=f(x),f n(x)=f[f n(x)](n∈N*),+1已知偶函数g(x)的定义域为(﹣∞,0)∪(0,+∞),g(1)=0,当x>0且x≠1时,g(x)=f2018(x).(1)求f2(x),f3(x),f4(x),f2018(x);(2)求出函数y=g(x)的解析式;(3)若存在实数a、b(a<b),使得函数g(x)在[a,b]上的值域为[mb,ma],求实数m的取值范围.【分析】(1)根据函数关系代入计算进行求解即可;(2)由偶函数的定义,计算可得所求解析式;(3)根据函数奇偶性和单调性的性质,结合函数的值域关系进行求解即可.【解答】解:(1)因为函数,(x)=f[f n(x)](n∈N*),f1(x)=,定义f1(x)=f(x),f n+1f2(x)=f[f1(x)]==,(x≠0且x≠1),f3(x)=f[f2(x)]==x,(x≠0且x≠1),f4(x)=f[f3(x)]=,(x≠0且x≠1),(x)=f i(x)(i=2,3,4),故对任意的n∈N•,有f3n+i=f2(x)=1﹣,(x≠0且x≠1);于是f2018(x)=f3×672+2(2)当x>0且x≠1时,g(x)=f2018(x)=1﹣,又g(1)=0,由g(x)为偶函数,当x<0时,﹣x>0,g(x)=g(﹣x)=1+,可得g(x)=;(3)由于y=g(x)的定义域为(﹣∞,0)∪(0,+∞),又a<b,mb<ma,可知a与b同号,且m<0,进而g(x)在[a,b]递减,且a<b<0,当a,b∈(0,1)时,g(x)=1﹣为增函数,故,即m==,得a﹣1=b﹣1,即a=b,与a<b矛盾,∴此时a,b不存在;函数y=g(x)的图象,如图所示.由题意,有,故a,b是方程1+=mx的两个不相等的负实数根,即方程mx2﹣x﹣1=0在(﹣∞,0)上有两个不相等的实根,于是,解得﹣<m<0.综合上述,得实数m的取值范围为(﹣,0).21.对于无穷数列{a n},记T={x|x=a j﹣a i,i<j},若数列{a n}满足:“存在t∈T,使得只要a m﹣a k=t(m,k∈N*,m>k),必有a m+1﹣a k+1=t”,则称数列具有性质P(t).(1)若数列{a n}满足,判断数列{a n}是否具有性质P(2)?是否具有性质P(4)?说明理由;(2)求证:“T是有限集”是“数列{a n}具有性质P(0)”的必要不充分条件;(3)已知{b n}是各项均为正整数的数列,且{b n}既具有性质P(2),又具有性质P(5),求证:存在正整数N,使得a N,a N+1,a N+2,…,a N+K,…是等差数列.【分析】(1)由,可得a2﹣a1=2,但a3﹣a2=﹣1≠2,数列{a n}不具有性质P(2);同理可判断数列{a n}具有性质P(4);(2)举例“周期数列1,1,2,2,1,1,2,2,…,T={﹣1,0,1}是有限集,利用新定义可证数列{a n}不具有性质P(0),即不充分性成立;再证明其必要性即可;(3)依题意,数列{b n}是各项为正整数的数列,且{b n}既具有性质P(2),又具有性质P(5),可证得存在整数N,使得b N,b N+1,b N+2,…,b N+k,…是等差数列.【解答】解:(1)∵,a2﹣a1=2,但a3﹣a2=﹣1≠2,数列{a n}不具有性质P(2);同理可得,数列{a n}具有性质P(4).(2)证明:(不充分性)对于周期数列1,1,2,2,1,1,2,2,…,T={﹣1,0,1}是有限集,但是由于a2﹣a1=0,a3﹣a2=1,所以不具有性质P(0);(必要性)因为数列{a n}具有性质P(0),所以一定存在一组最小的且m>k,满足a m﹣a k=0,即a m=a k由性质P(0)的含义可得a m+1=a k+1,a m+2=a k+2,…,a2m﹣k﹣1=a m﹣1,a2m﹣k=a m,…所以数列{a n}中,从第k项开始的各项呈现周期性规律:a k,a k+1,…,a m﹣1为一个周期中的各项,所以数列{a n}中最多有m﹣1个不同的项,所以T 最多有个元素,即T 是有限集;(3)证明:因为数列{b n }具有性质P (2),数列{b n }具有性质P (5), 所以存在M′、N′,使得b M'+p ﹣b M '=2,b N'+q ﹣b N '=5, 其中p ,q 分别是满足上述关系式的最小的正整数,由性质P (2),P (5)的含义可得,b M'+p +k ﹣b M'+k =2,b N'+q +k ﹣b N'+k =5, 若M'<N',则取k=N'﹣M',可得b N'+p ﹣b N '=2; 若M'>N',则取k=M'﹣N',可得b M'+q ﹣b M '=5.记M=max {M',N'},则对于b M ,有b M +p ﹣b M =2,b M +q ﹣b M =5,显然p ≠q , 由性质P (2),P (5)的含义可得,b M +p +k ﹣b M +k =2,b N +q +k ﹣b N +k =5, 所以b M +qp ﹣b M =(b M +qp ﹣b M +(q ﹣1)p )+(b M +(q ﹣1)p ﹣b M +(q ﹣2)p ) +…+(b M +p ﹣b M )=2qb M +qp ﹣b M =(b M +pq ﹣b M +(p ﹣1)q )+ (b M +(p ﹣1)q ﹣b M +(p ﹣2)q )+…+(b M +q ﹣b M )=5p 所以b M +qp =b M +2q=b M +5p . 所以2q=5p ,又p ,q 是满足b M +p ﹣b M =2,b M +q ﹣b M =5的最小的正整数, 所以q=5,p=2,b M +2﹣b M =2,b M +5﹣b M =5, 所以,b M +2+k ﹣b M +k =2,b M +5+k ﹣b M +k =5,所以,b M +2k =b M +2(k ﹣1)+2=…=b M +2k ,b M +5k =b M +5(k ﹣1)+5=…=b M +5k , 取N=M +5,若k 是偶数,则b N +k =b N +k ;若k 是奇数,则b N +k =b N +5+(k ﹣5)=b N +5+(k ﹣5)=b N +5+(k ﹣5)=b N +k , 所以,b N +k =b N +k ,所以b N ,b N +1,b N +2,…,b N +k ,…是公差为1的等差数列。
2018-2019学年上海市浦东新区建平中学高一(上)期中数学试卷一、填空题1.设全集∪={1,2,3,4,5,6},集合A={2,4,6},则∁U A=.2.不等式<0的解集是.3.已知集合A={﹣1,0,2},B={a2+1},若B⊄A,则实数a的值为.4.用列举法写出集合A={y|y=x2﹣1,x∈Z,|x|≤1}=5.已知不等式x2﹣ax+b≤0的解集为[2,3],则a+b=6.命题“如果a≠0,那么a2>0”的逆否命题为.7.已知集合A={(x,y)|y=x+1,x∈R},B={(x,y)|y=3﹣x.x∈R},则A∩B=.8.若“x>1”是“x≥a”的充分不必要条件,则a的取值范围为.9.已知集合A={x||x﹣1|≤1},B={x|ax=2},若A∪B=A,则实数a的取值集合为10.已知集合{x|(x﹣2)(x2﹣2x+a)=0,x∈R}中的所有元素之和为2,则实数a的取值集合为.11.已知正实数x,y满足x+y=1,则﹣的最小值是12.若不等式x+4≤a(x+y)对任意x>0,y>0恒成立,则a的取值范围是.二、选择题13.“x>1”是“”成立的()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14.若实数a、b满足条件a>b,则下列不等式一定成立的是()A.<B.a2>b2C.ab>b2D.a3>b315.设集合P={m|﹣1<m≤0},Q={m|mx2+2mx﹣1<0}对任意x∈R恒成立,则P与Q的关系是()A.P⊄Q B.Q⊄P C.P=Q D.P∩Q=∅16.已知集合A={1,2,3,…n)(n∈N*},集合B={j1,j2,…j k)(k≥2,k∈N*)是集合A的子集,若1≤j1<j2<…<j m≤n且j i+1﹣j i≥m(i=1,2,……,k﹣1),满足集合B的个数记为n(k⊕m),则7(3⊕2)=()A.9B.10C.11D.12三、解答题17.已知x,y是实数,求证:x2+y2≥2x+2y﹣2.18.已知全集U=R,集合A={x|x2﹣x﹣12<0},B={y|y=,x∈R},求A∩B,A∪(∁U B).19.已知命题p:关于x的一元二次方程x2﹣2x+|m﹣2|=0有两个不相等的实数根;命题q:关于x的一元二次方程x2﹣mx+|a+1|+|a﹣3|=0对于任意实数a都没有实数根.(1)若命题p为真命题,求实数m的取值范围;(2)若命题p和命题q中有且只有一个为真命题,求实数m的取值范围.20.已知集合A={x|x2﹣x﹣2≥0},集合B={x|(1﹣m2)x2+2mx﹣1<0,m∈R}.(1)当m=2时,求集合∁R A和集合B;(2)若集合B∩Z为单元素集,求实数m的取值集合;(3)若集合(A∩B)∩Z的元素个数为n(n∈N*)个,求实数m的取值集合.21.已知集合P的元素个数为3n(n∈N*)个且元素为正整数,将集合P分成元素个数相同且两两没有公共元素的三个集合A、B、C,即P=A∪B∪C,A∩B=∅,A∩C=∅,B∩C=∅,其中A={a1,a2,…,a n},B={b1,b2,…b n},C={c1,c2,…,c n}.若集合A、B、C中的元素满足c1<c2<…<c n,a k+b k=c k,k=1,2,…n,则称集合P为“完美集合”.(1)若集合P={1,2,3},Q={1,2,3,4,5,6},判断集合P和集合Q是否为“完美集合”?并说明理由;(2)已知集合P={1,x,3,4,5,6}为“完美集合”,求正整数x的值;(3)设集合P={x|1≤x≤3n,n≥2,n∈N*}①证明:集合P为“完美集合”的一个必要条件是n=4k或n=4k+1(k∈N*)②判断当n=4时,集合P是否为“完美集合”,如果是,求出所有符合条件的集合C;如果不是,请说明理由.2018-2019学年上海市浦东新区建平中学高一(上)期中数学试卷参考答案与试卷解析一、填空题1.【解答】解:全集∪={1,2,3,4,5,6},集合A={2,4,6},则∁U A={1,3,5}.故答案为:{1,3,5}.2.【解答】解:∵<0,∴(x﹣1)(x+2)<0,解得:﹣2<x<1,故不等式的解集是(﹣2,1),故答案为:(﹣2,1).3.【解答】解:若B⊂A,则①a2+1=﹣1,a∈∅;②a2+1=0,a∈∅;③a2+1=2,a=±1;∵B⊄A,∴a≠±1.故答案为:a≠±1.4.【解答】解:∵|x|≤1,且x∈Z;∴x=﹣1,0,或1;∴x2=0,或1;∴y=﹣1,或0;∴A={﹣1,0}.故答案为:{﹣1,0}.5.【解答】解:不等式x2﹣ax+b≤0的解集为[2,3],∴方程x2﹣ax+b=0的实数根为2和3,∴,a=5,b=6;∴a+b=11.故答案为:11.6.【解答】解:原命题“如果a≠0,那么a2>0”,∴其逆否命题为:“若a2≤0,则a=0”.故答案为:若a2≤0,则a=0.7.【解答】解:A∩B={(x,y)|}={(1,2)}.故答案为:{(1,2)}.8.【解答】解:若“x>1”是“x≥a”的充分不必要条件,则a≤1,故答案为:a≤19.【解答】解:A={x|0≤x≤2},①B=∅,a=0,②B≠∅,B={},0<≤2,≥,∴a≥1,故实数a的取值集合为[1,+∞)∪{0}.故答案为:[1,+∞)∪{0}.10.【解答】解:∵集合{x|(x﹣2)(x2﹣2x+a)=0,x∈R}中的所有元素之和为2,∴x2﹣2x+a=0的解为x=0或无解,∴a=0或Δ=4﹣4a<0,解得a>1.∴实数a的取值集合为{a|a=0或a>1}.故答案为:{a|a=0或a>1}.11.【解答】解:正实数x,y满足x+y=1,则﹣===()[x+(y+1)]﹣4=(5+)﹣4=当且仅当且x+y=1即y=,x=时取得最小值是/故答案为:12.【解答】解:∵不等式x+4≤a(x+y),x>0,y>0,∴a≥=,令=t>0,可得:f(t)=.f′(t)===.可知:t=时函数f(t)取得最大值,=4.f(0)=0.∴0<f(t)≤4.∵不等式x+4≤a(x+y)对任意x>0,y>0恒成立,∴a的取值范围是a≥4.故答案为:[4,+∞).二、选择题13.【解答】解:若x>1,则0<,则成立,即充分性成立,若当x<0时,成立,但x>1不成立,即必要性不成立,即“x>1”是“”成立的充分不必要条件,故选:A.14.【解答】解:根据题意,依次分析选项:对于A、a=1,b=﹣1时,有>成立,故A错误;对于B、a=1,b=﹣2时,有a2<b2成立,故B错误;对于C、a=1,b=﹣2时,有ab<b2成立,故C错误;对于D、由不等式的性质分析可得若a>b,必有a3>b3成立,则D正确;故选:D.15.【解答】解:∵集合P={m|﹣1<m≤0},Q={m|mx2+2mx﹣1<0}对任意x∈R恒成立,∴Q={m|﹣1<m≤0}.∴P与Q的关系是P=Q.故选:C.16.【解答】解:由题意可得n=7,k=3,m=2,那么集合A={1,2,3,4,5,6,7};集合B={j1,j2,j3},1≤j1<j2≤7,j i+1﹣j i≥2满足集合B的个数列罗出来,可得:{1,3,5},{1,3,6},{1,3,7},{1,4,6},{1,4,7};{1,5,7},{2,4,6},{2,4,7},{2,5,7},{3,5,7},故选:B.三、解答题17.【解答】证明:因为x2﹣2x+1=(x﹣1)2≥0,可得x2≥2x﹣1,y2﹣2y+1=(y﹣1)2≥0,可得y2≥2y﹣1,所以x2+y2≥2x+2y﹣2.18.【解答】解:A={x|﹣3<x<4};∵x4+1≥2x2;∴;∴B={y|y≥2};∴A∩B=[2,4),∁U B={y|y<2};∴A∪(∁U B)=(﹣∞,4).19.【解答】解:(1)命题p:关于x的一元二次方程x2﹣2x+|m﹣2|=0有两个不相等的实数根,可得Δ=12﹣4|m﹣2|>0,解得﹣1<m<5;(2)命题q:关于x的一元二次方程x2﹣mx+|a+1|+|a﹣3|=0对于任意实数a都没有实数根,可得﹣x2+mx=|a+1|+|a﹣3|,由|a+1|+|a﹣3|≥|a+1﹣a+3|=4,可得﹣x2+mx﹣4≥0无实数解,可得Δ=m2﹣16<0,即﹣4<m<4,命题p和命题q中有且只有一个为真命题,可得或,即有4≤m<5或﹣4<m≤﹣1.20.【解答】解:集合A={x|x2﹣x﹣2≥0}={x|x≥2或x≤﹣1},集合{x|(1﹣m2)x2+2mx﹣1<0,m∈R}={x|[(1+m)x﹣1][(1﹣m)x+1]<0}(1)当m=2时,集合∁R A={x|﹣1<x<2};集合B={x|x>1或x<};(2)因为集合B∩Z为单元素集,且0∈B,所以,解得m=0,当m=0时,经验证,满足题意.故实数m的取值集合为{0}(3)集合(A∩B)∩Z的元素个数为n(n∈N*)个,等价于(1﹣m2)x2+2mx﹣1<0在(﹣∞,﹣1]∪[2,+∞)上有整数解,所以令f(x)=(1﹣m2)x2+2mx﹣1,依题意有1﹣m2≤0或或,解得m<﹣或m>0.21.【解答】解:(1)将P分为集合{1}、{2}、{3},满足条件,是完美集合.将Q分成3个,每个中有两个元素,若为完美集合,则a1+b1=c1、a2+b2=c2,Q中所有元素之和为21,21÷2=c1+c2=10.5,不符合要求;(2)若集合A={1,4},B={3,5},根据完美集合的概念知集合C={6,7},若集合A={1,5},B={3,6},根据完并集合的概念知集合C={4,11},若集合A={1,3},B={4,6},根据完并集合的概念知集合C={5,9},故x的一个可能值为7,9,11中任一个;(3)①证明:P中所有元素之和为1+2+…+3n==a1+b1+c1+a2+b2+c2+…+a n+b n+c n=2(c1+c2+…+c n﹣1+c n),∵c n=3n,∴=c1+c2+…+c n﹣1+3n,∴=c1+c2+…+c n﹣1,等号右边为正整数,则等式左边9n(n﹣1)可以被4整除,∴n=4k或n﹣1=4k,即n=4k或n=4k+1;②p是完美集合,A={1,4,3,2},B={6,5,8,10},C={7,9,11,12}或A={1,2,4,3},B={5,8,7,9},C={6,10,11,12}或A={2,4,3,1},B={6,5,7,11},C={8,9,10,12}.。
2016-2017学年上海市浦东新区建平中学高三(上)期中数学试卷一.填空题1.(3分)已知R为实数集,M={x|x2﹣2x<0},N={x|x≥1},则M∩(∁R N)=.2.(3分)函数y=+log3(1+x)的定义域为.3.(3分)不等式的解集是.4.(3分)已知θ是第三象限角,若sinθ=﹣,则tan的值为.5.(3分)已知log a b=﹣1,则a+4b的最小值为.6.(3分)函数y=f(x)是奇函数且周期为3,f(﹣1)=1,则f(2017)=.7.(3分)函数cos(﹣x)=,那么sin2x=.8.(3分)函数f(x)=log2(2﹣)(x>0)的反函数f﹣1(x)=.9.(3分)若2arcsin(5x﹣2)=,则x=.10.(3分)已知直线x=,x=都是函数y=f(x)=sin(ωx+φ)(ω>0,﹣π<φ≤π)的对称轴,且函数f(x)在区间[,}上单调递减,则φ=.11.(3分)已知函数f(x)=x++3,x∈N*,在x=5时取到最小值,则实数a的所有取值的集合为.12.(3分)函数f(x)=cos x,对任意的实数t,记f(x)在[t,t+1]上的最大值为M(t),最小值为m(t),则函数h(t)=M(t)﹣m(t)的值域为.13.(3分)已知函数y=f(x),y=g(x)的值域均为R,有以下命题:①若对于任意x∈R都有f[f(x)]=f(x)成立,则f(x)=x.②若对于任意x∈R都有f[f(x)]=x成立,则f(x)=x.③若存在唯一的实数a,使得f[g(a)]=a成立,且对于任意x∈R都有g[f(x)]=x2﹣x+1成立,则存在唯一实数x0,使得g(ax0)=1,f(x0)=a.④若存在实数x0,y0,f[g(x0)]=x0,且g(x0)=g(y0),则x0=y0.其中是真命题的序号是.(写出所有满足条件的命题序号)14.(3分)关于x的方程(2017﹣x)(1999+x)=2016恰有两个根为x1、x2,且x1、x2分别满足3x1=a﹣3x1和log3(x2﹣1)3=a﹣3x2,则x1+x2+a=.二.选择题15.(3分)“2a>2b”是“log2a>log2b”的()条件.A.充分不必要B.必要不充分C.充要D.既不充分也不必要16.(3分)已知集合M={x|9x﹣4•3x+1+27=0},N={x|log2(x+1)+log2x=log26},则M、N的关系是()A.M⊊N B.N⊊M C.M=N D.不确定17.(3分)若y=f(x)是R上的偶函数,y=g(x)是R上的奇函数,它们都是周期函数,则下列一定正确的是()A.函数y=g[g(x)]是偶函数,函数y=f(x)g(x)是周期函数B.函数y=g[g(x)]是奇函数,函数y=f[g(x)]不一定是周期函数C.函数y=g[g(x)]是偶函数,函数y=f[g(x)]是周期函数D.函数y=g[g(x)]是奇函数,函数y=f(x)g(x)是周期函数18.(3分)如图,半径为1的半圆O与等边三角形ABC夹在两平行线l1,l2之间,l∥l1,l与半圆相交于F,G两点,与三角形ABC两边相交于E,D两点.设弧的长为x(0<x<π),y=EB+BC+CD,若l从l1平行移动到l2,则函数y=f(x)的图象大致是()A.B.C.D.三.解答题19.(8分)已知函数f(x)=|2x﹣a|+2;(1)若不等式f(x)<6的解集为(﹣1,3),求a的值;(2)在(1)的条件下,对任意的x∈R,都有f(x)>t﹣f(﹣x),求t的取值范围.20.(8分)在△ABC中,角A,B,C所对的边长分别为a,b,c,且cos.(1)若a=3,b=,求c的值;(2)若f(A)=sinA(cosA﹣sinA),求f(A)的取值范围.21.(10分)某厂生产某种产品的年固定成本为250万元,每生产x千件,需另投入成本C(x)(万元),若年产量不足80千件,C(x)的图象是如图的抛物线,此时C(x)<0的解集为(﹣30,0),且C(x)的最小值是﹣75,若年产量不小于80千件,C(x)=51x+﹣1450,每千件商品售价为50万元,通过市场分析,该厂生产的商品能全部售完;(1)写出年利润L(x)(万元)关于年产量x(千件)的函数解析式;(2)年产量为多少千件时,该厂在这一商品的生产中所获利润最大?22.(10分)已知函数f(x)=x|x﹣a|的定义域为D,其中a为常数;(1)若D=R,且f(x)是奇函数,求a的值;(2)若a≤﹣1,D=[﹣1,0],函数f(x)的最小值是g(a),求g(a)的最大值;(3)若a>0,在[0,3]上存在n个点x i(i=1,2,…,n,n≥3),满足x1=0,x n=3,x1<x2<…<x n,使|f(x1)﹣f(x2)|+|f(x2)﹣f(x3)|+…+|f(x n﹣1)﹣f(x n)|=,求实数a的取值.23.(10分)已知函数f(x)=其中P,M是非空数集,且P∩M=∅,设f(P)={y|y=f(x),x∈P},f(M)={y|y=f(x),x∈M}.(I)若P=(﹣∞,0),M=[0,4],求f(P)∪f(M);(II)是否存在实数a>﹣3,使得P∪M=[﹣3,a],且f(P)∪f(M)=[﹣3,2a﹣3]?若存在,请求出满足条件的实数a;若不存在,请说明理由;(III)若P∪M=R,且0∈M,I∈P,f(x)是单调递增函数,求集合P,M.2016-2017学年上海市浦东新区建平中学高三(上)期中数学试卷参考答案与试题解析一.填空题1.(3分)已知R为实数集,M={x|x2﹣2x<0},N={x|x≥1},则M∩(∁R N)=(0,1).【解答】解:∵x2﹣2x<0⇒0<x<2;∴M={x|x2﹣2x<0}={x|0<x<2};N={x|x≥1}⇒C R N={x|x<1}.所以:M∩(C R N)=(0,1)故答案为:(0,1).2.(3分)函数y=+log3(1+x)的定义域为(﹣1,2] .【解答】解:,解得:x∈(﹣1,2]故答案为:(﹣1,2]3.(3分)不等式的解集是[1,3﹚.【解答】解:不等式等价于解得x∈[1,3)故答案为:[1,3﹚4.(3分)已知θ是第三象限角,若sinθ=﹣,则tan的值为﹣3.【解答】解:∵θ是第三象限角,若sinθ=﹣,∴cosθ=﹣,∴tan===﹣3.故答案是:﹣3.5.(3分)已知log a b=﹣1,则a+4b的最小值为4.【解答】解:log a b=﹣1,可得ab=1.a,b>0.a+4b≥2=4.当且仅当a=4b=2时取等号.表达式的最小值为:4.故答案为:4.6.(3分)函数y=f(x)是奇函数且周期为3,f(﹣1)=1,则f(2017)=﹣1.【解答】解:y=f(x)是奇函数,即f(﹣x)=﹣f(x),∴f(1)=﹣f(﹣1)=﹣1,由y=f(x)周期为3,f(2017)=f(672×3+1)=f(1)=﹣1,故答案为:﹣1.7.(3分)函数cos(﹣x)=,那么sin2x=.【解答】解:∵cos(﹣x)=cosx+sinx=,∴可得:sinx+cosx=,∴两边平方可得:1+sin2x=,解得:sin2x=.故答案为:.8.(3分)函数f(x)=log2(2﹣)(x>0)的反函数f﹣1(x)=(x<1).【解答】解:由y=log2(2﹣)(x>0),解得x=(y<1),把x与y互换可得:y=(x<1).∴原函数的反函数为:(x<1).故答案为:(x<1).9.(3分)若2arcsin(5x﹣2)=,则x=.【解答】解:因为2arcsin(5x﹣2)=,所以sin[arcsin(5x﹣2)]=,即5x ﹣2=,所以x=.故答案为.10.(3分)已知直线x=,x=都是函数y=f(x)=sin(ωx+φ)(ω>0,﹣π<φ≤π)的对称轴,且函数f(x)在区间[,}上单调递减,则φ=.【解答】解:直线x=,x=都是函数f(x)=sin(ωx+ϕ)(ω>0,﹣π<ϕ≤π)的对称轴,且函数f(x)在区间[,]上单调递减,所以T=2×(﹣)=;所以ω==6,并且1=sin(6×+ϕ),﹣π<ϕ≤π,所以,ϕ=;故答案为:.11.(3分)已知函数f(x)=x++3,x∈N*,在x=5时取到最小值,则实数a的所有取值的集合为[20,30] .【解答】解:∵f(x)=x++3,x∈N*,∴f′(x)=1﹣=,当a≤0时,f′(x)≥0,函数f(x)为增函数,最小值为f(x)min=f(1)=4+a,不满足题意,当a>0时,令f′(x)=0,解得x=,当0<x<时,即f′(x)<0,函数单调递减,当x>时,即f′(x)>0,函数单调递增,∴当x=时取最小值,∵x∈N*,∴x取离最近的正整数使f(x)达到最小,∵x=5时取到最小值,∴5<<6,或4<≤5∴f(5)≤f(6)且f(4)≥f(5),∴4++3≥5++3且5++3≤6++3解得20≤a≤30故答案为:[20,30]12.(3分)函数f(x)=cos x,对任意的实数t,记f(x)在[t,t+1]上的最大值为M(t),最小值为m(t),则函数h(t)=M(t)﹣m(t)的值域为.【解答】解:解:函数f(x)=cos x的周期为T==4,(1)当4n﹣1≤t≤4n,n∈Z,区间[t,t+1]为增区间,则有m(t)=cos,M(t)=cos=sin,(2)当4n<t<4n+1,n∈Z,①若4n<t≤4n+,则M(t)=1,m(t)=sin,②若4n+<t<4n+1,则M(t)=1,m(t)=sin,(3)当4n+1≤t≤4n+2,则区间[t,t+1]为减区间,则有M(t)=cos,m(t)=sin;(4)当4n+2<t<4n+3,则m(t)=﹣1,①当4n+2<t≤4n+时,M(t)=cos,②当4n+<t<4n+3时,M(t)=sin;则有h(t)=M(t)﹣m(t)=当4n﹣1≤t≤4n,h(t)的值域为[1,],当4n<t≤4n+,h(t)的值域为[1﹣,1),当4n+<t<4n+1,h(t)的值域为(1﹣,1),当4n+1≤t≤4n+2,h(t)的值域为[1,],当4n+2<t≤4n+时,h(t)的值域为[1﹣,1),当4n+<t<4n+3时,h(t)的值域为[1﹣,1).综上,h(t)=M(t)﹣m(t)的值域为.故答案是:.13.(3分)已知函数y=f(x),y=g(x)的值域均为R,有以下命题:①若对于任意x∈R都有f[f(x)]=f(x)成立,则f(x)=x.②若对于任意x∈R都有f[f(x)]=x成立,则f(x)=x.③若存在唯一的实数a,使得f[g(a)]=a成立,且对于任意x∈R都有g[f(x)]=x2﹣x+1成立,则存在唯一实数x0,使得g(ax0)=1,f(x0)=a.④若存在实数x0,y0,f[g(x0)]=x0,且g(x0)=g(y0),则x0=y0.其中是真命题的序号是①③④.(写出所有满足条件的命题序号)【解答】解:①令t=f(x),则对于任意x∈R都有f[f(x)]=f(x)成立可化为:f(t)=t,即f(x)=x,故①为真命题;②令,显然能满足题设条件,当x≠0,有f(x)=,不满足结论;故②为假命题;③假设存在实数x0,∵f(x0)=a,f(g(a))=a;∴g(a)=x0;g(f(x0))=﹣x0+1;=[g(a)]2﹣g(a)+1;而f(g(a))=a,∴命题成立;故③正确;④∵,g(x0)=g(y0);∴x0=y0;故④正确;故答案为:①③④14.(3分)关于x的方程(2017﹣x)(1999+x)=2016恰有两个根为x1、x2,且x1、x2分别满足3x1=a﹣3x1和log3(x2﹣1)3=a﹣3x2,则x1+x2+a=61.【解答】解:方程(2017﹣x)(1999+x)=2016可化为﹣x2+16x+2017×1999﹣2016=0,∴x1+x2=16.∵x1满足3x1=a﹣3x1,x2满足log3(x2﹣1)3=a﹣3x2,∴=﹣1﹣(x1﹣1),log3(x2﹣1)=﹣1﹣(x2﹣1).∴x1﹣1+x2﹣1=﹣1,∴a=45,∴x1+x2+a=16+45=61.故答案为61.二.选择题15.(3分)“2a>2b”是“log2a>log2b”的()条件.A.充分不必要B.必要不充分C.充要D.既不充分也不必要【解答】解:由“2a>2b”得a>b,由“log2a>log2b”得a>b>0,则“2a>2b”是“log2a>log2b”的必要不充分条件,故选:B.16.(3分)已知集合M={x|9x﹣4•3x+1+27=0},N={x|log2(x+1)+log2x=log26},则M、N的关系是()A.M⊊N B.N⊊M C.M=N D.不确定【解答】解:集合M={x|9x﹣4•3x+1+27=0},可得9x﹣4•3x+1+27=0,即(3x)2﹣12•3x+27=0,解得3x=3,3x=9,解得x=1,x=2.M={1,2}.N={x|log2(x+1)+log2x=log26},log2(x+1)+log2x=log26,可得x(x+1)=6,x>0.解得x=2.N={2}.∴N⊊M.故选:B.17.(3分)若y=f(x)是R上的偶函数,y=g(x)是R上的奇函数,它们都是周期函数,则下列一定正确的是()A.函数y=g[g(x)]是偶函数,函数y=f(x)g(x)是周期函数B.函数y=g[g(x)]是奇函数,函数y=f[g(x)]不一定是周期函数C.函数y=g[g(x)]是偶函数,函数y=f[g(x)]是周期函数D.函数y=g[g(x)]是奇函数,函数y=f(x)g(x)是周期函数【解答】解:∵y=f(x)是R上的偶函数,y=g(x)是R上的奇函数,故有g(﹣x)=﹣g(x),且f(﹣x)=f(x).令m(x)=g[g(x)],n(x)=f(x)g(x),则m(﹣x)=g[g(﹣x)]=g[﹣g(x)]﹣g[g(x)]=﹣m(x),故m(x)为奇函数,故排除A、C;∵f(x)和g(x)都是周期函数,设他们的周期的最小公倍数为t,即f(x+t)=f(x),g(x+t)=g(x),n(x+t)=f(x+t)g(x+t)=f(x)g(x)=n(x),故n(x)=f(x)g(x)一定为周期函数,故排除B,故选:D.18.(3分)如图,半径为1的半圆O与等边三角形ABC夹在两平行线l1,l2之间,l∥l1,l与半圆相交于F,G两点,与三角形ABC两边相交于E,D两点.设弧的长为x(0<x<π),y=EB+BC+CD,若l从l1平行移动到l2,则函数y=f(x)的图象大致是()A.B.C.D.【解答】解:当x=0时,y=EB+BC+CD=BC=;当x=π时,此时y=AB+BC+CA=3×=2;当x=时,∠FOG=,三角形OFG为正三角形,此时AM=OH=,在正△AED中,AE=ED=DA=1,∴y=EB+BC+CD=AB+BC+CA﹣(AE+AD)=3×﹣2×1=2﹣2.如图.又当x=时,图中y0=+(2﹣)=>2﹣2.故当x=时,对应的点(x,y)在图中红色连线段的下方,对照选项,D正确.故选:D.三.解答题19.(8分)已知函数f(x)=|2x﹣a|+2;(1)若不等式f(x)<6的解集为(﹣1,3),求a的值;(2)在(1)的条件下,对任意的x∈R,都有f(x)>t﹣f(﹣x),求t的取值范围.【解答】解:(1)f(x)<6,即|2x﹣a|<4,∵不等式f(x)<6的解集为(﹣1,3),∴,∴a=2;(2)∵f(x)>t﹣f(﹣x),∴t<f(x)+f(﹣x),∴t<|2x﹣2|+|﹣2x﹣2|+4,∵|2x﹣2|+|﹣2x﹣2|+4≥4+4=8,∴t<8.20.(8分)在△ABC中,角A,B,C所对的边长分别为a,b,c,且cos.(1)若a=3,b=,求c的值;(2)若f(A)=sinA(cosA﹣sinA),求f(A)的取值范围.【解答】解:(1)在△ABC中,A+B+C=π,∴cos=cos=sin=,∴=,即B=,∵a=3,b=,cosB=,∴由余弦定理b2=a2+c2﹣2accosB,即7=9+c2﹣3c,整理得:c2﹣3c+2=0,解得:c=1或c=2;(2)f(A)=sinA(cosA﹣sinA)=sin2A﹣=sin(2A+)﹣,由(1)得B=,∴A+C=,即A∈(0,),∴2A+∈(,),∴sin(2A+)∈(﹣1,1],∴f(A)∈(﹣,],∴f(A)的取值范围是(﹣,].21.(10分)某厂生产某种产品的年固定成本为250万元,每生产x千件,需另投入成本C(x)(万元),若年产量不足80千件,C(x)的图象是如图的抛物线,此时C(x)<0的解集为(﹣30,0),且C(x)的最小值是﹣75,若年产量不小于80千件,C(x)=51x+﹣1450,每千件商品售价为50万元,通过市场分析,该厂生产的商品能全部售完;(1)写出年利润L(x)(万元)关于年产量x(千件)的函数解析式;(2)年产量为多少千件时,该厂在这一商品的生产中所获利润最大?【解答】解:(1)∵每件商品售价为0.005万元,∴x千件商品销售额为0.005×1000x万元,①当0<x<80时,根据年利润=销售收入﹣成本,∴L(x)=(0.05×1000x)﹣x2﹣10x﹣250=﹣x2+40x﹣250;②当x≥80时,根据年利润=销售收入﹣成本,∴L(x)=(0.05×1000x)﹣51x﹣+1450﹣250=1200﹣(x+).综合①②可得,;(2)由(1)可知,;①当0<x<80时,L(x)=﹣x2+40x﹣250=﹣(x﹣60)2+950∴当x=60时,L(x)取得最大值L(60)=950万元;②当x≥80时,L(x)=1200﹣(x+)≤1200﹣2=1200﹣200=1000,当且仅当,即x=100时,L(x)取得最大值L(100)=1000万元.综合①②,由于950<1000,∴当产量为10万件时,该厂在这一商品中所获利润最大,最大利润为1000万元.22.(10分)已知函数f(x)=x|x﹣a|的定义域为D,其中a为常数;(1)若D=R,且f(x)是奇函数,求a的值;(2)若a≤﹣1,D=[﹣1,0],函数f(x)的最小值是g(a),求g(a)的最大值;(3)若a>0,在[0,3]上存在n个点x i(i=1,2,…,n,n≥3),满足x1=0,x n=3,x1<x2<…<x n,使|f(x1)﹣f(x2)|+|f(x2)﹣f(x3)|+…+|f(x n﹣1)﹣f(x n)|=,求实数a的取值.【解答】解:(1)∵f(x)是R上的奇函数,∴f(﹣1)+f(1)=﹣|﹣1﹣a|+|1﹣a|=0,∴|a﹣1|=|a+1|,解得a=0.∴f(x)=x|x|,经过验证满足题意;(2)a≤﹣1,D=[﹣1,0],函数f(x)=x(x﹣a)=﹣,①a≤﹣2时,对称轴x=≤﹣1,函数f(x)在D上单调递增,∴f(x)的最小值是f(﹣1)=﹣(﹣1﹣a)=a+1,则g(a)≤﹣2+1=﹣1,故g(a)的最大值为﹣1;②﹣2<a≤﹣1时,对称轴x=∈,函数f(x)在(,﹣)上单调递增,在[﹣1,]单调递减;∴f(x)的最小值是f()=﹣,则g(a)≤﹣,故g(a)的最大值为﹣;(3)a>0,函数f(x)=x|x﹣a|的图象可由f(x)=x|x|的图象右移a个单位得到.而f(x)=x|x|=,x>0时递增,x<0时递增,且f(x)的图象连续,则函数f(x)=x|x﹣a|在[0,3]递增,即有|f(x1)﹣f(x2)|+|f(x2)﹣f(x3)|+…+|f(x n﹣1)﹣f(x n)|=,化为﹣(f(x1)﹣f(x2)+f(x2)﹣f(x3)+…+f(x n﹣1)﹣f(x n))=,即﹣(f(0)﹣f(3))=,则3|3﹣a|﹣0=,解得a=或.则实数a的取值为{,}.23.(10分)已知函数f(x)=其中P,M是非空数集,且P∩M=∅,设f(P)={y|y=f(x),x∈P},f(M)={y|y=f(x),x∈M}.(I)若P=(﹣∞,0),M=[0,4],求f(P)∪f(M);(II)是否存在实数a>﹣3,使得P∪M=[﹣3,a],且f(P)∪f(M)=[﹣3,2a﹣3]?若存在,请求出满足条件的实数a;若不存在,请说明理由;(III)若P∪M=R,且0∈M,I∈P,f(x)是单调递增函数,求集合P,M.【解答】解:(I)∵P=(﹣∞,0),∴f(P)={y|y=|x|,x∈(﹣∞,0)}=(0,+∞),∵M=[0,4],∴f(M)={y|y=﹣x2+2x,x∈[0,4]}=[﹣8,1].∴f(P)∪f(M)=[﹣8,+∞)(II)若﹣3∈M,则f(﹣3)=﹣15∉[﹣3,2a﹣3],不符合要求∴﹣3∈P,从而f(﹣3)=3∵f(﹣3)=3∈[﹣3,2a﹣3]∴2a﹣3≥3,得a≥3若a>3,则2a﹣3>3>﹣(x﹣1)2+1=﹣x2+2x∵P∩M=∅,∴2a﹣3的原象x0∈P且3<x0≤a∴x0=2a﹣3≤a,得a≤3,与前提矛盾∴a=3此时可取P=[﹣3,﹣1)∪[0,3],M=[﹣1,0),满足题意(III)∵f(x)是单调递增函数,∴对任意x<0,有f(x)<f(0)=0,∴x∈M ∴(﹣∞,0)⊆M,同理可证:(1,+∞)⊆P若存在0<x0<1,使得x0∈M,则1>f(x0)=﹣+2x0>x0,于是[x0,﹣+2x0]⊆M记x1=﹣+2x0∈(0,1),x2=﹣+2x1,…∴[x0,x1]∈M,同理可知[x1,x2]∈M,…=﹣+2x n,得1﹣x n+1=1+﹣2x n=(1﹣)2;由x n+1∴1﹣x n=(1﹣)2=(1﹣x n﹣2)22=…=(1﹣x0)2n对于任意x∈[x0,1],取[log2log(1﹣x0)(1﹣x)﹣1,log2log(1﹣x0)(1﹣x)]中的自然数n x,则x∈[xn x,xn x+1]⊆M∴[x0,1)⊆M综上所述,满足要求的P,M必有如下表示:P=(0,t)∪[1,+∞),M=(﹣∞,0]∪[t,1),其中0<t<1或者P=(0,t]∪[1,+∞),M=(﹣∞,0]∪(t,1),其中0<t<1或者P=[1,+∞),M=(﹣∞,1]或者P=(0,+∞),M=(﹣∞,0]。
2017-2018学年上海市建平中学高三(上)9月月考数学试卷一、填空题1.(3分)在(x+a)5的二项式展开式中,x2的系数与x3的系数相同,则非零实数a的值为.2.(3分)袋中共有15个除颜色外完全相同的球,其中10个白球5个红球,从袋中任取2个球,所取的2个球中恰有1个白球,1个红球的概率为.3.(3分)设双曲线C的焦点在x轴上,渐近线方程为y=x,则其离心率为;若点(4,2)在C上,则双曲线C的方程为.4.(3分)已知集合{x|(x﹣1)(x2﹣x+a)=0,x∈R}中的所有元素之和为1,则实数a的取值集合为.5.(3分)已知x∈C,且x5﹣1=0,则=.6.(3分)设,则=.7.(3分)若复数z满足,则复数|z﹣1﹣i|的最大值为.8.(3分)在平面上,过点P作直线l的垂线所得的垂足称为点P的直线上的投影,由区域中的点在直线x+y﹣2=0上的投影构成的线段记为AB,则|AB|=.9.(3分)已知△ABC,若存在△A1B1C1,满足,则称△A1B1C1是△ABC的一个“友好”三角形.在满足下述条件的三角形中,存在“友好”三角形的是:(请写出符合要求的条件的序号)①A=90°,B=60°,C=30°;②A=75°,B=60°,C=45°;③A=75°,B=75°,C=30°.10.(3分)集合,若B⊆A,则实数a的取值范围是.11.(3分)在△ABC中,D、E分别是AB,AC的中点,M是直线DE上的动点,若△ABC的面积为1,则•+2的最小值为.12.(3分)已知函数f(x)=(a>0且α≠1)在R上单调递减,且关于x的方程|f(x)|=2﹣x恰有两个不相等的实数解,则a的取值范围是.二、选择题13.(3分)若a、b为实数,则ab(a﹣b)<0成立的一个充要条件是()A.B.C.D.14.(3分)l1、l2是空间两条直线,α是平面,以下结论正确的是()A.如果l1∥α,l2∥α,则一定有l1∥l2B.如果l1⊥l2,l2⊥α,则一定有l1⊥αC.如果l1⊥l2,l2⊥α,则一定有l1∥αD.如果l1⊥α,l2∥α,则一定有l1⊥l215.(3分)已知数列{a n}共有5项,满足a1>a2>a3>a4>a5≥0,且对任意i,j(1≤i≤j≤5),有a i﹣a j仍是该数列的某一项,则下列命题中,假命题的序号是()A.数列{a n}中一定存在一项为0B.存在1≤i<j≤5,使得ia i=ja jC.数列{a n}一定是等差数列D.集合A={x|x=a i+a j,1≤i<j≤5}中元素个数为15.16.(3分)已知函数f(x)=,有下列四个结论:①对任意x∈D,f(x)+f(﹣x)=0恒成立;②存在m∈(0,1),使得方程|f(x)|=m有两个不等实根;③对任意x1,x2∈D,若x1≠x2,则一定有f(x1)=f(x2);④对任意k∈(1,+∞),函数g(x)=f(x)﹣kx有三个零点.上述结论正确的个数为()A.1B.2C.3D.4三、解答题17.如图,在长方体ABCD﹣A1B1C1D1中,AB=8,BC=5,AA1=4,平面α截长方体得到一个矩形EFGH,且A1E=D1F=2,AH=DG=5.(1)求截面EFGH把该长方体分成的两部分体积之比;(2)求直线AF与平面α所成角的正弦值.18.已知数列{a n}是首项等于的等比数列,公比q∈N*,S n是它的前n项和,满足S4=5S2.(1)求数列{a n}的通项公式;(2)设b n=log a a n(a>0且a≠1),求数列{b n}的前n项和T n的最值.19.某校兴趣小组在如图所示的矩形区域ABCD内举行机器人拦截挑战赛,在E 处按方向释放机器人甲,同时在A处按某方向释放机器人乙,设机器人乙在Q处成功拦截机器人甲.若点Q在矩形区域ABCD内(包含边界),则挑战成功,否则挑战失败.已知AB=18米,E为AB中点,机器人乙的速度是机器人甲的速度的2倍,比赛中两机器人均按匀速直线运动方式行进,记与的夹角为θ.(1)若θ=60°,AD足够长,则如何设置机器人乙的释放角度才能挑战成功?(结果精确到0.1°)(2)如何设计矩形区域ABCD的宽AD的长度,才能确保无论θ的值为多少,总可以通过设置机器人乙的释放角度使机器人乙在矩形区域ABCD内成功拦截机器人甲?20.设椭圆M:的左顶点为A、中心为O,若椭圆M过点,且AP⊥PO.(1)求椭圆M的方程;(2)若△APQ的顶点Q也在椭圆M上,试求△APQ面积的最大值;(3)过点A作两条斜率分别为k1,k2的直线交椭圆M于D,E两点,且k1k2=1,求证:直线DE恒过一个定点.21.已知集合A={x|x2﹣x﹣2≤0,x∈Z},集合B={x|lg(x2+x+8)=1},集合C={x|x=ab,a∈A,b∈B}.(1)用列举法表示集合C;(2)设集合C的含n个元素所有子集为C n,记有限集合M的所有元素和为S (M),求S(C1)+S(C2)+…+S(C n)的值.(3)已知集合P,Q是集合C的两个不同子集,若P不是Q的子集,且Q不是P的子集,求所有不同的有序集合对(P,Q)的个数n(P,Q).2017-2018学年上海市建平中学高三(上)9月月考数学试卷参考答案与试题解析一、填空题1.(3分)在(x+a)5的二项式展开式中,x2的系数与x3的系数相同,则非零实数a的值为1.【分析】利用(x+a)5二项式展开式的通项公式写出展开式中含x2的系数和x3的系数,列方程求出a的值.=•x5﹣r•a r,【解答】解:(x+a)5的二项式展开式中,通项公式为T r+1∴含x2的系数为•a3,x3的系数为•a2,由题意知•a3=•a2,即10a3=10a2,解得a=1或a=0;∴非零实数a的值为1.故答案为:1.2.(3分)袋中共有15个除颜色外完全相同的球,其中10个白球5个红球,从袋中任取2个球,所取的2个球中恰有1个白球,1个红球的概率为.【分析】从袋中任取2个球,基本事件总数n=,所取的2个球中恰有1个白球,1个红球包含的基本事件个数m=,由此能求出所取的2个球中恰有1个白球,1个红球的概率.【解答】解:袋中共有15个除颜色外完全相同的球,其中10个白球5个红球,从袋中任取2个球,基本事件总数n==105,所取的2个球中恰有1个白球,1个红球包含的基本事件个数m=,∴所取的2个球中恰有1个白球,1个红球的概率为p==.故答案为:.3.(3分)设双曲线C的焦点在x轴上,渐近线方程为y=x,则其离心率为;若点(4,2)在C上,则双曲线C的方程为.【分析】根据双曲线渐近线和a,b的关系建立方程进行求解即可求出离心率的大小,利用待定系数法求λ,即可得到结论.【解答】解:∵双曲线C的焦点在x轴上,渐近线方程为y=x,∴=,即==e2﹣1=,则e2=,则e=,设双曲线方程为﹣y2=λ,λ>0,∵若点(4,2)在C上,∴λ==8﹣4=4,即双曲线方程为﹣y2=4,即,故答案为:4.(3分)已知集合{x|(x﹣1)(x2﹣x+a)=0,x∈R}中的所有元素之和为1,则实数a的取值集合为{0}∪(,+∞).【分析】利用分类讨论的思想①当a=0时,集合只有0和1两个元素,故满足所有的元素和为1.②当f(x)=x2﹣x+a没有零点,即)x2﹣x+a=0没有实根,故△<0,进一步求出结果.【解答】解:集合{x|(x﹣1)(x2﹣x+a)=0,x∈R}中的所有元素之和为1,则:①当a=0时,集合只有0和1两个元素,故满足所有的元素和为1.②当f(x)=x2﹣x+a没有零点,即)x2﹣x+a=0没有实根.故△<0,即1﹣4a<0解得:a.综合①②得:,故答案为:{0}∪(,+∞)5.(3分)已知x∈C,且x5﹣1=0,则=4,或﹣1.【分析】由x5﹣1=(x﹣1)(x4+x3+x2+x+1)=0,得x=1,或x4+x3+x2+x+1=0,进而得到答案.【解答】解:∵x∈C,且x5﹣1=(x﹣1)(x4+x3+x2+x+1)=0,故x=1,或x4+x3+x2+x+1=0,当x=1时,=4,当x4+x3+x2+x+1=0时,==﹣1,故=4,或﹣1故答案为:4,或﹣1.6.(3分)设,则=1+.【分析】由已知求出|z n|,再由无穷递缩等比数列所有项和的求解方法求解.【解答】解:∵,∴=,则==.故答案为:1+.7.(3分)若复数z满足,则复数|z﹣1﹣i|的最大值为.【分析】设出z=a+bi(a,b∈R),则由,得z在复平面内对应点的轨迹,再由|z﹣1﹣i|的几何意义求解.【解答】解:设z=a+bi(a,b∈R),则由,得a2+b2+2a≤0,即(a+1)2+b2≤1.复数z在复平面内对应点的轨迹如图:∴复数|z﹣1﹣i|的最大值为|PC|+1=.故答案为:.8.(3分)在平面上,过点P作直线l的垂线所得的垂足称为点P的直线上的投影,由区域中的点在直线x+y﹣2=0上的投影构成的线段记为AB,则|AB|=3.【分析】作出不等式组对应的平面区域,利用投影的定义,利用数形结合进行求解即可.【解答】解:作出不等式组对应的平面区域如图:(阴影部分),区域内的点在直线x+y﹣2=0上的投影构成线段R′Q′,即SAB,而R′Q′=RQ,由得Q(﹣1,1)由即R(2,﹣2),则|AB|=|QR|==3,故答案为:3.9.(3分)已知△ABC,若存在△A1B1C1,满足,则称△A1B1C1是△ABC的一个“友好”三角形.在满足下述条件的三角形中,存在“友好”三角形的是②:(请写出符合要求的条件的序号)①A=90°,B=60°,C=30°;②A=75°,B=60°,C=45°;③A=75°,B=75°,C=30°.【分析】满足,则有A1=±A,B1=±B,C1=±C逐一验证选项即可.【解答】解:满足,则有A1=±A,B1=±B,C1=±C.对于①,cosA=cos90°=0,显然不成立.对于②,可取满足题意.对于③,经验证不满足.故答案为:②.10.(3分)集合,若B⊆A,则实数a的取值范围是{a|1<a} .【分析】根据B⊆A,建立条件关系即可求实数a的取值范围.【解答】解:集合,化简集合A={x|x2﹣5x+4≤0}=[1,4].∵B⊆A,当B=∅时,则4(a﹣2)2﹣4a<0,可得:1<a<4.当B≠∅时,f(x)=x2﹣2(a﹣2)x+a≤0有解.则4(a﹣2)2﹣4a≥0,f(1)≥0,f(4)≥0,,可得:3<a综上可得:实数a的取值范围是{a|1<a}.故答案为:{a|1<a≤}.11.(3分)在△ABC中,D、E分别是AB,AC的中点,M是直线DE上的动点,若△ABC的面积为1,则•+2的最小值为.【分析】由三角形的面积公式,S△ABC=2S△MBC,则S△MBC=,根据三角形的面积公式及向量的数量积,利用余弦定理,即可求得则•+2,利用导数求得函数的单调性,即可求得则•+2的最小值;方法二:利用辅助角公式及正弦函数的性质,即可求得•+2的最小值.【解答】解:∵D、E是AB、AC的中点,∴A到BC的距离=点A到BC的距离的一半,∴S△ABC =2S△MBC,而△ABC的面积1,则△MBC的面积S△MBC=,S△MBC=丨MB丨×丨MC丨sin∠BMC=,∴丨MB丨×丨MC丨=.∴•=丨MB丨×丨MC丨cos∠BMC=.由余弦定理,丨BC丨2=丨BM丨2+丨CM丨2﹣2丨BM丨×丨CM丨cos∠BMC,显然,BM、CM都是正数,∴丨BM丨2+丨CM丨2≥2丨BM丨×丨CM丨,∴丨BC丨2=丨BM丨2+丨CM丨2﹣2丨BM丨×丨CM丨cos∠BMC=2×﹣2×..∴•+2≥+2×﹣2×=,方法一:令y=,则y′=,令y′=0,则cos∠BMC=,此时函数在(0,)上单调减,在(,1)上单调增,∴cos∠BMC=时,取得最小值为,•+2的最小值是,方法二:令y=,则ysin∠BMC+cos∠BMC=2,则sin(∠BMC+α)=2,tanα=,则sin(∠BMC+α)=≤1,解得:y≥,•+2的最小值是,故答案为:.12.(3分)已知函数f(x)=(a>0且α≠1)在R上单调递减,且关于x的方程|f(x)|=2﹣x恰有两个不相等的实数解,则a的取值范围是[,]∪{} .【分析】利用函数是减函数,根据对数的图象和性质判断出a的大致范围,再根据f(x)为减函数,得到不等式组,利用函数的图象,方程的解的个数,推出a的范围.【解答】解:函数f(x)=(a>0且α≠1)在R上单调递减,则:;解得,≤a≤.由图象可知,在[0,+∞)上,|f(x)|=2﹣x有且仅有一个解,故在(﹣∞,0)上,|f(x)|=2﹣x同样有且仅有一个解,当3a>2即a>时,联立|x2+(4a﹣3)x+3a|=2﹣x,则△=(4a﹣2)2﹣4(3a﹣2)=0,解得a=或1(舍去),当1≤3a≤2时,由图象可知,符合条件,综上:a的取值范围为[,]∪{},故答案为:[,]∪{}.二、选择题13.(3分)若a、b为实数,则ab(a﹣b)<0成立的一个充要条件是()A.B.C.D.【分析】先判断p⇒q与q⇒p的真假,再根据充要条件的定义给出结论;也可判断命题p与命题q所表示的范围,再根据“谁大谁必要,谁小谁充分”的原则,判断命题p与命题q的关系.【解答】解:ab(a﹣b)<0⇔a2b﹣ab2<0⇔a2b<ab2⇔⇔<故选:D.14.(3分)l1、l2是空间两条直线,α是平面,以下结论正确的是()A.如果l1∥α,l2∥α,则一定有l1∥l2B.如果l1⊥l2,l2⊥α,则一定有l1⊥αC.如果l1⊥l2,l2⊥α,则一定有l1∥αD.如果l1⊥α,l2∥α,则一定有l1⊥l2【分析】由空间中直线与直线、直线与平面、平面与平面的关系逐一核对四个选项得答案.【解答】解:若l1∥α,l2∥α,则有l1∥l2或l1与l2相交或l1与l2异面,故A错误;如果l1⊥l2,l2⊥α,则有l1∥α或l1⊂α,故B、C错误;如果l1⊥α,则l1垂直α内的所有直线,又l2∥α,则过l2与α相交的平面交α于a,则l2∥a,∴l1⊥l2,故D正确.故选:D.15.(3分)已知数列{a n}共有5项,满足a1>a2>a3>a4>a5≥0,且对任意i,j(1≤i≤j≤5),有a i﹣a j仍是该数列的某一项,则下列命题中,假命题的序号是()A.数列{a n}中一定存在一项为0B.存在1≤i<j≤5,使得ia i=ja jC.数列{a n}一定是等差数列D.集合A={x|x=a i+a j,1≤i<j≤5}中元素个数为15.【分析】根据题意:对任意i,j(1≤i≤j≤5),有a i﹣a j仍是该数列的某一项,因此0∈{a n},由于a4﹣a5=a4∈{a n},(a4>0),可得a3﹣a4=a4,即a3=2a4,以此类推可得:a2=3a4,a1=4a4.分析选项即可判断出结论.【解答】解:根据题意:对任意i,j(1≤i≤j≤5),有a i﹣a j仍是该数列的某一项,∴a i﹣a i=0,∴当a5=0时,则a4﹣a5=a4∈{a n},(a4>0).必有a3﹣a4=a4,即a3=2a4,而a2﹣a3=a3或a4,若a2﹣a3=a3,则a2﹣a4=3a4,而3a4≠a3,a4,a5,舍去;若a2﹣a3=a4∈{a n},此时a2=3a4,同理可得a1=4a4.可得数列{a n}为:4a4,3a4,2a4,a4,0(a4>0);据此分析选项:易得A、B、C正确;对于D、集合A={x|x=a i+a j,1≤i≤j≤5}={8a4,7a4,6a4,5a4,4a4,3a4,2a4,a4,0(a4>0)}中共有9个元素,D错误;故选:D.16.(3分)已知函数f(x)=,有下列四个结论:①对任意x∈D,f(x)+f(﹣x)=0恒成立;②存在m∈(0,1),使得方程|f(x)|=m有两个不等实根;③对任意x1,x2∈D,若x1≠x2,则一定有f(x1)=f(x2);④对任意k∈(1,+∞),函数g(x)=f(x)﹣kx有三个零点.上述结论正确的个数为()A.1B.2C.3D.4【分析】通过函数的基本性质﹣﹣奇偶性和单调性,对选项进行逐一验证即可【解答】解:∵函数f(x)=(x∈R)是奇函数,∴任意x∈R,等式f(﹣x)+f(x)=0恒成立,故①正确;令m=,|f(x)|=,可解得,x=1或x=﹣1,故②正确;当x≥0时,f(x)=,f'(x)=>0,故原函数在[0,+∞)单调递增当x<0时,f(x)=,f'(x)=>0,故原函数在(﹣∞,0)单调递增,故函数在R上单调递增,对任意x1,x2∈D,若x1≠x2,则一定有f(x1)≠f(x2);故③错误;由③中分析可得:f'(x)∈(0,1],故对任意k∈(1,+∞),函数y=f(x)的图象与y=kx只有原点一个交点,即函数g(x)=f(x)﹣kx有一个零点,故④错误.故选:B.三、解答题17.如图,在长方体ABCD﹣A1B1C1D1中,AB=8,BC=5,AA1=4,平面α截长方体得到一个矩形EFGH,且A1E=D1F=2,AH=DG=5.(1)求截面EFGH把该长方体分成的两部分体积之比;(2)求直线AF与平面α所成角的正弦值.【分析】(1)由题意,平面α把长方体分成两个高为5的直四棱柱,转化求解体积推出结果即可.(2)解法一:作AM⊥EH,垂足为M,证明HG⊥AM,推出AM⊥平面EFGH.通过计算求出AM=4.AF,设直线AF与平面α所成角为θ,求解即可.解法二:以DA、DC、DD1所在直线分别为x轴、y轴、z轴建立空间直角坐标系,求出平面α一个法向量,利用直线AF与平面α所成角为θ,通过空间向量的数量积求解即可.【解答】(本题满分(14分),第1小题满分(6分),第2小题满分8分)解:(1)由题意,平面α把长方体分成两个高为5的直四棱柱,,…(2分),…(4分)所以,.…(6分)(2)解法一:作AM⊥EH,垂足为M,由题意,HG⊥平面ABB1A1,故HG⊥AM,所以AM⊥平面EFGH.…(2分)=10,)因为,,所以S△AEH因为EH=5,所以AM=4.…(4分)又,…(6分)设直线AF与平面α所成角为θ,则.…(7分)所以,直线AF与平面α所成角的正弦值为.…(8分)解法二:以DA、DC、DD1所在直线分别为x轴、y轴、z轴建立空间直角坐标系,则A(5,0,0),H(5,5,0),E(5,2,4),F(0,2,4),…(2分)故,,…(3分)设平面α一个法向量为,则即所以可取.…(5分)设直线AF与平面α所成角为θ,则.…(7分)所以,直线AF与平面α所成角的正弦值为.…(8分)18.已知数列{a n}是首项等于的等比数列,公比q∈N*,S n是它的前n项和,满足S4=5S2.(1)求数列{a n}的通项公式;(2)设b n=log a a n(a>0且a≠1),求数列{b n}的前n项和T n的最值.【分析】(1)公比q∈N*,q≠1,由S4=5S2.可得=,解得q.(2)b n=log a a n=(n﹣5)log a2,利用等差数列的求和公式可得数列{b n}的前n项和T n=log a2,对a分类讨论,利用二次函数与对数函数的单调性即可得出.【解答】解:(1)公比q∈N*,q≠1,∵S4=5S2.∴=,解得q=2.∴a n==2n﹣5.(2)b n=log a a n=(n﹣5)log a2,∴数列{b n}的前n项和T n=log a2=log a2,a>1时,(T n)min=T4=T5=﹣10log a2.0<a<1时,(T n)max=T4=T5=﹣10log a2.19.某校兴趣小组在如图所示的矩形区域ABCD内举行机器人拦截挑战赛,在E 处按方向释放机器人甲,同时在A处按某方向释放机器人乙,设机器人乙在Q处成功拦截机器人甲.若点Q在矩形区域ABCD内(包含边界),则挑战成功,否则挑战失败.已知AB=18米,E为AB中点,机器人乙的速度是机器人甲的速度的2倍,比赛中两机器人均按匀速直线运动方式行进,记与的夹角为θ.(1)若θ=60°,AD足够长,则如何设置机器人乙的释放角度才能挑战成功?(结果精确到0.1°)(2)如何设计矩形区域ABCD的宽AD的长度,才能确保无论θ的值为多少,总可以通过设置机器人乙的释放角度使机器人乙在矩形区域ABCD内成功拦截机器人甲?【分析】(1)利用正弦定理,即可求解;(2)以AB所在直线为x轴,AB中垂线为y轴,建平面直角坐标系,求出Q 的轨迹方程,即可得出结论.【解答】解:(1)△AEQ中,AQ=2EQ,∠AEQ=120°…(2分)由正弦定理,得:所以…(4分)所以所以应在矩形区域ABCD内,按照与夹角为25.7°的向量方向释放机器人乙,才能挑战成功…(6分)(2)以AB所在直线为x轴,AB中垂线为y轴,建平面直角坐标系,设Q(x,y)(y≥0)…(8分)由题意,知AQ=2EQ,所以所以(x﹣3)2+y2=36(y≥0)…(11分)即点Q的轨迹是以(3,0)为圆心,6为半径的上半圆在矩形区域ABCD内的部分所以当AD≥6米时,能确保无论θ的值为多少,总可以通过设置机器人乙的释放角度使机器人乙在矩形区域ABCD内成功拦截机器人甲…(14分)20.设椭圆M:的左顶点为A、中心为O,若椭圆M过点,且AP⊥PO.(1)求椭圆M的方程;(2)若△APQ的顶点Q也在椭圆M上,试求△APQ面积的最大值;(3)过点A作两条斜率分别为k1,k2的直线交椭圆M于D,E两点,且k1k2=1,求证:直线DE恒过一个定点.【分析】(1)利用AP⊥OP,可知k AP•k OP=﹣1,A点坐标为(﹣a,0),得a,求出b,然后求解椭圆方程.(2)求出AP的方程x﹣y+1=0,通过Q是椭圆M上的点,故可设,然后利用三角形的面积求解最大值即可.(3)直线AD方程为y=k1(x+1),代入x2+3y2=1,求出D、E坐标,得到直线DE的方程,利用直线系得到定点坐标.(法二)若DE垂直于y轴,则x E=﹣x D,y E=y D,此时与题设矛盾.若DE不垂直于y轴,可设DE的方程为x=ty+s,将其代入x2+3y2=1,利用韦达定理结合斜率关系推出DE的方程为x=ty﹣2,推出直线DE过定点(﹣2,0).【解答】解:(1)由AP⊥OP,可知k AP•k OP=﹣1,又A点坐标为(﹣a,0),故,可得a=1,…(2分)因为椭圆M过P点,故,可得,所以椭圆M的方程为.…(4分)(2)AP的方程为,即x﹣y+1=0,由于Q是椭圆M上的点,故可设,…(6分)所以…(8分)=当,即时,S取最大值.△APQ的最大值为.…(10分)故S△APQ(3)直线AD方程为y=k1(x+1),代入x2+3y2=1,可得,,又x A=﹣1,故,,…(12分)同理可得,,又k1k2=1且k1≠k2,可得且k1≠±1,所以,,,直线DE的方程为,…(14分)令y=0,可得.故直线DE过定点(﹣2,0).…(16分)(法二)若DE垂直于y轴,则x E=﹣x D,y E=y D,此时与题设矛盾.若DE不垂直于y轴,可设DE的方程为x=ty+s,将其代入x2+3y2=1,可得(t2+3)y2+2tsy+s2﹣1=0,可得,…(12分)又,可得,…(14分)故,可得s=﹣2或﹣1,又DE不过A点,即s≠﹣1,故s=﹣2.所以DE的方程为x=ty﹣2,故直线DE过定点(﹣2,0).…(16分)21.已知集合A={x|x2﹣x﹣2≤0,x∈Z},集合B={x|lg(x2+x+8)=1},集合C={x|x=ab,a∈A,b∈B}.(1)用列举法表示集合C;(2)设集合C的含n个元素所有子集为C n,记有限集合M的所有元素和为S (M),求S(C1)+S(C2)+…+S(C n)的值.(3)已知集合P,Q是集合C的两个不同子集,若P不是Q的子集,且Q不是P的子集,求所有不同的有序集合对(P,Q)的个数n(P,Q).【分析】(1)先求出集合A,B,进而可得集合C={x|x=ab,a∈A,b∈B}(2)C的每一元素a在“总和”S(M)中均出现25次,进而可得答案;(3)集合C有26个子集,不同的有序集合对(P,Q)有26(26﹣1)个.去除满足P⊊Q和Q⊊P的元素个数,可得答案.【解答】解:(1)∵集合A={x|x2﹣x﹣2≤0,x∈Z}={﹣1,0,1,2},集合B={x|lg(x2+x+8)=1}={﹣2,1},集合C={x|x=ab,a∈A,b∈B}={﹣4,﹣2,﹣1,0,1,2}.(2)n∈N*时,对C的任一元素a,因为C共有6个元素,故含有元素a的子集为25个,故C的每一元素a在“总和”S(M)中均出现25次,故S(C1)+S(C2)+…+S(C n)=(﹣4﹣2﹣1+0+1+2)•25=﹣128;(3)集合C有26个子集,不同的有序集合对(P,Q)有26(26﹣1)个.若P⊊Q,并设Q中含有k(1≤k≤n,k∈N•)个元素,则满足P⊊Q的有序集合对(P,Q)有=36﹣26个.同理,满足Q⊊P的有序集合对(P,Q)有36﹣26个.故满足条件的有序集合对(P,Q)的个数为n(P,Q)=26(26﹣1)﹣2(36﹣26)=2702.。
绝密★启用前上海市浦东新区建平中学2018届高三上学期10月月考数学试题一、填空题:本大题共12小题,每小题5分,共20分).1.(5分)已知集合A={x|x<1},B={x|x≥0},则A∩B= .2.(5分)函数f(x)=log2(x﹣1)的定义域为.3.(5分)当x>0时,函数f(x)=x+x﹣1的值域为.4.(5分)“x>1”是“x>a”的充分不必要条件,则实数a的取值范围是.5.(5分)若函数f(x)是奇函数,且x<0时,f(x)=x﹣2,则f﹣1(3)= .6.(5分)已知集合A={x|x2﹣3x+2≤0,x∈Z},B={t|at﹣1=0},若A∪B=A,则实数a的取值集合为.7.(5分)已知函数f(x)=lg(ax2﹣4x+5)在(1,2)上为减函数,则实数a的取值集合为.8.(5分)已知不等式≤1的解集为A,若1∉A,则实数a的取值范围是.9.(5分)设函数f(x)=ln(1+|x|)﹣,若f(a)>f(2a﹣1),则实数a的取值范围是.10.(5分)若集合A={x|x2+4x+a=0},集合B={t|函数f(x)=4x2﹣8x+t(4﹣t)至多有一个零点},则A∪B的元素之和的函数关系式f(a)= .11.(5分)当m>0时,方程(mx﹣1)2﹣=m在x∈[0,1]上有且只有一个实根,则实数m的取值范围是.12.(5分)已知函数f(x)=,记函数g(x)=f(x)﹣t,若存在实数t,使得函数g(x)有四个零点,则实数a的取值范围是.二、选择题13.(5分)下列函数中,与函数y=10lgx的定义域和值域相同的是()A.y=B.y=C.y=D.y=14.(5分)命题:“若x2=1,则x=1”的逆否命题为()A.若x≠1,则x≠1或x≠﹣1 B.若x=1,则x=1或x=﹣1C.若x≠1,则x≠1且x≠﹣1 D.若x=1,则x=1且x=﹣115.(5分)若函数f(x)=ax2+bx+c在区间[0,1]上的最大值是M,最小值是m,则M﹣m()A.与b有关,且与c有关B.与b有关,但与c无关C.与b无关,且与c无关D.与b无关,但与c有关16.(5分)已知函数y=f(x)(x∈R),给出下列命题:①若f(x)既是奇函数又是偶函数,则f(x)=0;②若f(x)是奇函数,且f(﹣1)=f(1),则f(x)至少有三个零点;③若f(x)在R上不是单调函数,则f(x)不存在反函数;④若f(x)的最大值和最小值分别为M、m(m<M),则f(x)的值域为[m,M].则其中正确的命题个数是()A.1 B.2 C.3 D.4三、解答题17.已知U=R,P={x|>a},Q={x|x2﹣3x≤10}.(1)若a=1,求(∁U P)∩Q;(2)若P∩Q=P,求实数a的取值范围.18.已知函数f(x)=+(1)判断函数f(x)的奇偶性,并说明理由;(2)解不等式f(x)≥.19.某城市要建造一个边长为2km的正方形市民休闲OABC,将其中的区域ODC开挖成一个池塘,如图建立平面直角坐标系后,点D的坐标为(1,2),曲线OD是函数y=ax2图象的一部分,过对边OA上一点M的区域OABD内作一次函数y=kx+m(k>0)的图象,与线段DB 交于点N(点N不与点D重合),且线段MN与曲线OD有且只有一个公共点P,四边形MABN 为绿化风景区.(1)写出函数关系式m=f(k);(2)设点P的横坐标为t,将四边形MABN的面积S表示关于t的函数S=g(t),并求S的最大值.。
建平中学2018届高三第一学期期中考试高三英语试题命题人:高三英语备课组审题人:高三英语备课组说明:(1)本场考试时间120分钟,总分140分;(2)请认真答卷,并用规范字书写。
I. Listening ComprehensionSection ADirections: In Section A, you will hear ten short conversations between two speakers. At the end of each conversation, a question will be asked about what was said. The conversations and the questions will be spoken only once. After you hear a conversation and the question about it, read the four possible answers on your paper, and decide which one is the best answer to the question you have heard.1. A. It was moving. B. It was boring.C. It was interesting than TV programs.D. It was horrible.2. A. 85 dollars. B. 55 dollars. C. 80 dollars. D. 70 dollars.3. A. Her doctor. B. Her husband. C. Her boss. D. Her secretary.4. A. At the luggage claim area. B. At the boarding gate.C. At the reception desk.D. At the Customs.5. A. The library is generally locked on Friday afternoon.B. Something unusual happened in the library on Friday.C. The library is open to readers every day.D. Everyone can enter the library easily now.6. A. He came to the meeting. B. He planned the meeting.C. He had no idea about the meeting.D. He hasn’t come to the meeting yet.7. A. Jewels. B. Books. C. Shaver. D. Souvenirs.8. A. Buy a new motorcycle.B. Buy a second motorcycle.C. Save money for a new motorcycle.D. A new motorcycle can run faster than a used one.9. A. In the apartment. B. On the phone.C. At the real estate agency.D. Out of the apartment.10. A. Alex works very hard.B. Alex’s pay will be raised next month.C. The woman is unhappy about Alex’s salary.D. Alex will get 3,100 dollars next month.Section BDirections: In Section B, you will hear two short passages, and you will be asked three questions on each of the passage. The passages will be read twice, but the questions will be spoken only once. When you hear a question, read the four possible answers in your paper and decide which one would be the best answer to the question you have heard.Questions 11 through 13 are based on the following passage.11. A. Toothbrush. B. Wood. C. Peg. D. Metal.12. A. Because they could make beautiful keys.B. Because they wore some of their keys as rings.C. Because they designed locks and keys that were better at preventing thieves.D. Because they were invited by kings to design castle keys.13. A. By using smartphone apps. B. By using traditional metal keys.C. By using electronic keycards.D. By facial recognition.Questions 14 through 16 are based on the following passage.14. A. Kind and generous people. B. Residents of Delhi.C. Low-income citizens.D. Film fans.15. A. They lacked poetic creativity to put their feelings into words.B. They lived under such heavy pressure that they didn’t feel like writing at all.C. The idea of writing poems frightened them and made them lose themselves.D. They didn’t have the chance to confidently bring their poetic talent into play.16. A. They make migrant workers feel warm in a hustle and bustle world.B. They warm cold-hearted people up in the big world.C. They brighten the ordinary people up in the cold winter.D. They happen in over-populated cities with many poor citizens.Section CDirections:In section C, you will hear one longer conversation, and you will be asked four questions on it. The conversation will be read twice, but the questions will be spoken only once. When you hear a question, read the four possible answers on your paper and decide which one would be the best answer to the question you have heard.Questions 17 and 20 are based on the following conversation.17. A. Who to be invited to the farewell party.B. Gary’s farewell party.C. What to be done at the farewell party.D. Sending invitations to the farewell party.18. A. Oct. 21st. B. Oct. 28th. C. Oct. 25th. D. Oct. 26th.19. A. A book. B. Flowers. C. Dictionaries. D. A football.20. A. Gary. B. The class teacher. C. The classmates. D. The headmaster.II. Grammar and Vocabulary(20分)Section ADirections: After reading the passage below, fill in the blanks to make the passage coherent and grammatically correct. For the blanks with a given word, fill in each blank with the proper form of the given word; for the other blanks, use one word that best fits each blank.To have a fruitful discussion, teachers need to decide what seating arrangement is best for their own class and be prepared to experiment with different methods. (21)__________ method is adopted, it should help and be productive of dialogue between children as well as between teacher and child. Within the physical setting children and teachers should agree(22)________ a discussiontakes place.Why are rules necessary for discussion? This may be a question to ask the children. If children are given freedom to talk, why are there rules that will restrict that freedom? The golden rule is of course that one’s own freedom (23)_______ not interfere with the freedom of others. Individuals within a democratic community have equal rights. A child who talks all the time (24)_________(deny) the rights of others to be heard. Each person should be allowed an equal chance to speak and to put forward their own point of view and if we wish (25)_________(listen) to, then we should listen to others. There is no point giving a point of view (26)_________ someone is listening. (27)_________ of us are capable of listening to more than one person at a time, so another basic rule should be: only one person to speak at a time. Listening implies not only hearing the words but paying attention to the meaning of (28)___________ is being said. This is not a natural thing for children to do. School is typically a place where children learn to listen to the teacher but not to each other. The skills of listening need to be practiced. The ideal discussion, (29)________ _________ everyone listens to the speaker and then each is allowed to reply, is rare among adults, let alone children. It works (30)_______(well) when certain ground-rules for discussion are followed.Section BDirections: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.Most people get sweaty palms just staring at El Capitan, a breathtaking rock formation in Yosemite National Park, California. Alex Honnold’s stayed dry. And this June, he managed to climb the 900-meter vertical wall, pulling on edges barely big enough for ___31___.Honnold could not ___32___ any slips. That's because he carried nothing other than a bag of gymnasts’ chalk, to keep his fingers free of moisture. There was no rope to ___33___ him if he fell. After a four-hour ___34___ of power and precision, the 31-year-old safely challenged himself.El Capitan had been climbed ___35___ before, including by Honnold, but never in the way he has. In 2011, an American TV show about his earlier “free solos” drew seventeen million viewers. In climbing, “free” means using nothing but rocks for support. “Solo” means free of protection. It is the sport at its ___36___. In Yosemite, the birthplace of American climbing, Hannold has reached its peak. Praise from fellow climbers was ___37___ only by relief at his safe return.The achievement marks the latest in a series of milestones for sport climbing(竞技攀岩). In 2015, two other Americans Tommy Caldwell and Kevin Jorgeson, established a route up the Dawn Wall, El Capitan’s ___38___ part, after years of attempts. They made the front page of the New York Times and got congratulations from Barack Obama for the achievement. Last year, sport climbing was ___39___ accepted into the Olympic program for Tokyo 2020.These have strengthened climbing’s position in the sporting circle in America and elsewhere. Google has invited Jorgeson to give a motivational talk to its employees. Climbing gyms have appeared around the globe over the past decade, making the event safer and more ___40___ to ordinary people. The gyms have been particularly popular among youngsters, who pay more attention to experiences than to belongings.III. Reading Comprehension(45分)Section ADirections: 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 of phrase that best fits the context.At a certain age, you may feel as if you’re still at life’s beginning yet also disturbingly close to the ___41___. You feel keenly that there’s much left to do. You were going to win an Oscar, pick up a Nobel Prize in physics and get elected president, ___42___ you haven’t even gotten around to auditioning(试镜)for a film, taking a university physics ___43___ or brushing up on your politics.It’s almost enough to make you want to live forever. But then isn’t the real goal a life hugely increased not so much in ___44___ as in width? A life during which it’s ___45___ to pursue every one of a wide range of coexistent possibilities?It’s true. If you were immortal(永生的), you might eventually get to be a philosopher and a cantor and an actor and a psychoanalyst and a novelist. But don’t forget: over the vastly extended period, life would certainly not cease exposing you to still further of ___46___. When you finally entered psychoanalytic training in 2100, you’d have to give up any number of other new possibilities that might at that instant ___47___ themselves, such as joining an “expedition to Alpha Centauri, or learning to create art with the previously ___48___ colors recently made visible on the spectrum. You might have crossed one possibility off our list, but you’d have ___49___ three more. Hundreds of years in, you’d still feel as though you’d ___50___ moved beyond the opening stages of what life has to offer.Many activities you once loved, meanwhile, would fall out of fashion or out of reach. As an aging mortal, your knees might make it tough to run a marathon, causing you to ___51___ all the healthy racers. As permanently youthful immortal, ___52___, you might remain fit to run marathons over the centuries. But perhaps the beloved urban races of your youth would have long since disappeared and been ___53___ because of impossibly hot global temperatures and the fact that future civilizations find interplanetary relays far more ___54___. All of the things you once did have shelf lives. The longer you live, the more of them die, increasing the weight of the time that has flowed through your fingers.Many of us 60- and 70-somethings will remember George Burns’ quip goes: old age isn’t great but it sure beats the alternative. There’s also truth to the reverse. ___55___ isn’t great, but it sure beats the alternative.41. A. end B. interval C. milestone D. next42. A. but B. though C. since D. whereas43. A. prize B. exam C. principle D. course44. A. depth B. height C. length D. weight45. A. enjoyable B. necessary C. impracticable D. possible46. A. choices B. lessons C. challenges D. disturbances47. A. exclude B. face C. present D. ignore48. A. unattractive B. pale C. unimaginable D. unique49. A. added B. tried C. created D. identified50. A. actually B. hardly C. significantly D. vaguely51. A. encourage B. follow C. envy D. imitate52. A. by contrast B. as a result C. for instance D. in addition53. A. banned B. restored C. suspended D. feared54. A. time-saving B. exciting C. comfortable D. economical55. A. Future B. Youth C. Death D. ImmortalitySection BDirections: 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 you have just read.(A)Notices have been put up here and there in the village for the last fortnight announcing a meeting to discuss the yearly Flower Show, which has not been held in Fairacre for a number of years. Before I became the village schoolmistress here, the Flower Show appears to have been an event of some importance and people came from miles around to enjoy a day at Fairacre.I decided to go to the meeting, as the children in my school, I knew, used to play quite a large part in this village excitement and there were a number of special competitions, such as collecting wild flowers, making dolls’ house decorations or little gardens and so on, included in the program.It was a freezing, starlit night. By the time I arrived at the Village Hall, there were about ten people already there. The doctor was chairman of the meeting. A few men were warming their hands over the rather smoky oil stove, which was trying, somewhat inefficiently, to warm the room. The meeting was called for seven thirty---a most inconvenient time in my private opinion as it successfully upsets the evening and puts back the time of one’s evening meal. By a quarter to eight, only fifteen people had arrived.“I think we must begin,” the doctor said, turning his gentle smile upon us. He gave a short speech about the past glories of Fairarce’s Flower Show and his hopes that it might take place again. “Perhaps someone would put forward the suggestion that the Flower Show be restarted?” he suggested. There was a heavy silence, broken only by the movement of feet from the bench at the back. All fifteen of us , I noticed, were middle-aged. John Pringle, Mrs. Pringle’s only child, must have been the youngest among us and he is a man of nearly thirty. It was John who, at last, shyly answered the doctor’s request.“I’ll do it,” he said. “Propose we have a Flower Show then.” He sat down, pink and self-conscious, and the doctor thanked him sincerely. “Is there anybody else who agrees with this proposal?” Again that painful silence. It seemed as though we sat in a dream.“I’ll do it,” I said, when I could stand the waiting no longer. “Good! Good!” said the doctor cheerfully. “Let’s take a vote here then.” All fifteen raised their hands doubtfully. To look at our faces an outsider might reasonably have thought we were having the choice of hanging or the electric chair.56. What is the purpose of the meeting?A. To make arrangements for the next Flower Show.B. To get people’s ideas about the next Flower Show.C. To decide whether a Flower Show would be held again.D. To find out whether people would help with the Flower Show.57. What was the reason for the author’s attendance?A. The school children had always taken part in the Flower Show.B. She wanted to find out what the children could do to help.C. She wanted to know what special lessons to give the children.D. The school children might do more work in the school garden.58. Why did the author declare her support for Mr. Pringle’s proposal?A. It had become fairly clear that nobody else would.B. She was in a hurry to go home.C. She was the only one really interested in the matter.D. She felt sorry for the doctor.( B )Mapping AntarcticaAntarctica was on the map long before anyone ever laideyes on it. Nearly 2,400 years ago, ancient Greek philosopherssuch as Aristotle believed that a great continent must exist at thebottom of the world. They thought it was needed to balance outthe continents at the top of the world. In the 1500s, mapmakersoften included a fanciful continent they referred to as TerraIncognita(Latin for “unknown land”) at the bottom of theirmaps. But it was not until the 1800s ---- after explorers hadsighted and set foot on Antarctica ---- that mapmakers got down to the business of really mapping the continent, which is one-and-a-half times the size of the U.S..While the coastline could be mapped by ships sailing around the continent, it took airplanes ---- and later, satellites ---- to chart Antarctica’s vast interior (内陆). That job continues today. And it is a job that can still require a mapmaker, or cartographer, to put on boots and head out into the wild.Cole Kelleher is familiar with that. He is a cartographer with the Polar Geospatial Center (PGC),which is based at the University of Minnesota and has astaff at McMurdo Station. PGC teamed up with Googleto use the company’s Trekker technology to captureimages of Antarctica for the Internet giant’s popularfeature, Street View. A Trekker camera, which is the sizeof a basketball, is set about two feet above a backpack.The camera records images in all directions. “It weighsabout 50 pounds. I was out for two and a half days,hiking 10 to 12 hours each day,” says Kelleher. It was hard work, but really an incredible experience.” According to Kelleher there are plans to use the technology to create educational apps for museums.The PGC staff at McMurdo Station provides highly specialized mapmaking services for the U.S. Antarctic Program. For one project, Kelleher used satellite images to map huge cracks in the ice. That helped a team of researchers know whether they could safely approach their field camp on snowmobiles. Another recent project was to help recover a giant, high-tech helium (氦气) balloon used to carry scientific instruments high into the atmosphere. These balloons are launched in Antarctica because there is no danger that they will hurt anyone when they fall back down to Earth. Using satellite images, Kelleher and colleagues created maps of where the balloon could be found.Antarctica may no longer be Terra Incognita, but it still holds countless mysteries. Cartographers and the maps they make will continue to be essential in helping scientists unlock those secrets.59. From the passage, we can infer that Antarctic was on the map in the 1500s when ______.A. mapmakers knew it was much larger than the U.S.B. Aristotle named the continent Terra IncognitaC. no one had ever seen or been to the continentD. it was such an interesting continent as was often referred to60. Which of the following statements is NOT true according to the passage?A. It needs much work for the mapmakers to head out into the wild.B. The interior can only be mapped by planes and satellites.C. It is relatively easy to map Antarctica’s coastline by ship.D. Antarctic is a vast but still mysterious continent.61. The Polar Geospatial Center (PGC) works with Google initially ______.A. to capture images of Antarctica for Street ViewB. to test the company’s Trekker technologyC. to create educational apps for museumsD. to hike for an incredible experience62. The fourth paragraph mainly talks about ______.A. satellite images which are used to map huge cracks in the iceB. a high-tech helium balloon for carrying scientific instrumentsC. how to safely approach the researchers’ field camp and the balloonD. the specialized mapmaking services provided by the PGC staff(C)A therapy-animal trend attracts the United States. The San Francisco airport uses a pig to calm tired travelers. Universities nationwide bring dogs (and a donkey) onto campus to relieve students during finals. And that duck on a plane? It might be an emotional-support animal prescribed by a mental health professional.The trend, which has been gaining popularity hugely since its initial stirrings a few decades ago, is strengthened by a widespread belief that interaction with animals can reduce distress---whether it happens over brief physical contact at the airport or in long-term relationships at home. Certainly the groups offering up pets think so, as do some mental health professionals. But the popular embrace of pets as furry therapists is causing growing discomfort among some researchers in the field, who say it has raced far ahead of scientific evidence.Earlier this year in the Journal of Applied Developmental Science, an introduction to articles on “animal-assisted intervention” said research into its effectiveness “remains in its infancy.”A recent literature review by Molly Crossman, a Yale University doctoral candidate who recently wrapped up one study involving an 8-year-old dog named Pardner, cited a “vague body of evidence” that sometimes has shown positive short-term effects, often found no effect and occasionally identified higher rates of distress.Overall, Crossman wrote, animals seem to be helpful in a “small-to-medium” way, but it’s unclear whether the animals deserve the credit or something else is at play.“It’s a field that has been sort of carried forward by the beliefs of practitioners” who have seen patients’ mental health improve after working with or adopting animals, said James Serpell, director of the Centre for the Interaction of Animals and Society at the University of Pennsylvania School of Veterinary Medicine. “That kind of thing has almost driven the field, and the research is playingcatch-up . In other words, people are recognizing that stories aren’t enough.”Using animals in mental health setting is nothing new. In the 17th century, a Quaker-run retreat in England encouraged mentally ill patients to interact with animals on its grounds. Sigmund Freud often included one of his dogs in psychoanalysis sessions. Yet the subject did not become a research target until the American psychologist Boris Levinson began writing in the 1960s about the positive effect his dog Jingles had on patients.But the evidence to date is problematic, according to Crossman’s review and others before it. Most studies had small sample sizes, she wrote, and an “ alarming number” did not control for other possible reasons for a changed stress level, such as interaction with the animal’s human handler. Studies also tend to generalize across animals, she noted. If participants are measurably relieved by one golden retriever, that doesn’t mean another dog---or another species—will arouse the same response.63. According to the passage, what makes the therapy-animal trend more popular?A. It has been in existence for no less than twenty years.B. Mental health professionals have managed to cure patients with animals.C. It is widely assumed that staying with animals can make people happier.D. There is much related research to show that animals do good to some patients.64.Molly Crossman is quoted in the passage to_______.A. illustrate more scientific evidence is needed that animals are effective therapists.B. highlight the importance of practitioners’ beliefs in the field of animal therapiesC. question Srepell’s view that animals deserve the credit in helping patients.D. criticize people for their taking human-animal stories too seriously65. What can be inferred from the passage?A. Animal-assisted intervention turns out to be of more use than people think.B. It is hard to see how many reasons there are for people to benefit from animals.C. Research findings relating to one breed of dogs may not apply to another breed.D. Small sample sizes can sometimes produce reliable effects in human-animal studies.66. Which of the following might be the best title of the passage?A. More evidence found for dog-human relationshipB. Potential effects dogs have on patientsC. Therapeutic animal: nothing newD. Good dog, good therapist?Section CDirections: Read the following passage. Fill in each blank with a proper sentence given in the box. Each sentence can be used only once. Note that there are two more sentences than you need.Acid rain is now a familiar problem in the industrialized countries in Europe. Harmful gases like sulphur dioxide and nitrogen oxide are produced by power stations and cars. 67 Acid rain is also capable of dissolving some rocks and buildings made of soft rock, such as limestone, are particularly badly affected. The acid rain attacks the rock, and so carvings and statues are worn away more quickly.68 According to a report in the New Scientist, acid rain is being blamed for the rapid decay of ancient ruins in Mexico. The old limestone buildings in places like Chichen Itza, Tulum and Palenque are wearing away very quickly indeed. These sites are the remains of the buildings built by the Mayas between 250 BC and AD900, and the spectacular ruins of Mayan civilization are visited by thousands of tourists every year.The acid rain is said to be caused by pollution from oil wells in the Gulf of Mexico. Car exhaust gases are also a problem. Local volcanic eruptions make the problem even worse. Nevertheless, with enough money and effort, researchers say that many of the problems could be solved and the rate of dissolving reduced. 69Mexico’s current lack of funds is also partly due to oil. The country has rich oil fields and a few years ago, when oil was expensive, Mexico was selling large quantities of oil to the USA and earning a lot of money. The government was therefore able to borrow huge sums of money from banks around the world, thinking they would have no problem repaying their debts. However, the price of oil then dropped, and Mexico has been left owing enormous sums of money and with not enough income from oil sales to pay back the loans. 70IV. Summary writingDirections: Read the following passage. Summarize the main idea and main point(s) of the passage in no more than 60 words. Use your own words as far as possible.Ellie is a psychologist, and a good one at that. Smile in a certain way, and she knows precisely what your smile means. She listens to what you say, processes every word, works out the meaning of your pitch, your tone, your posture, everything. She is at the top of her game but, according to a new study, her greatest advantage is that she is not human.When faced with tough or potentially embarrassing questions, people often do not tell doctors what they need to hear. Yet the researchers behind Ellie, led by Jonathan Gratch at the Institute for Creative Technologies, in Los Angeles, suspected from their years of monitoring human interactions with computers that people might be more willing to talk if presented with an avatar, that is, a virtual figure. To test this idea, they put 239 people in front of Ellie to have a chat with her about their lives. Half were told (truthfully) they would be interacting with an artificially intelligent virtual human (AIVH); the others were told (falsely) that Ellie was a bit like puppet, and was having her strings pulled remotely by a person.Dr. Gratch and his colleagues report that, though every participant interacted with the same avatar, their experiences differed markedly based on what they believed they were dealing with. Those who thought Ellie was under the control of a human operator reported greater fear of disclosing personal information, and said they managed more carefully what they expressed during the session, than did those who believed they were simply interacting with a computer.V. Translation(15分)Directions: Translate the following sentences into English, using the words in the brackets.1. 二个月后他才适应了国外的生活。
2018-2019学年上海市浦东新区建平中学高一(上)期中数学试卷试题数:21.满分:01.(填空题.3分)设全集∪={1.2.3.4.5.6}.集合A={2.4.6}.则∁U A=___ .2.(填空题.3分)不等式x−1x+2<0的解集是___ .3.(填空题.3分)已知集合A={-1.0.2}.B={a2+1}.若B⊄A.则实数a的值为___ .4.(填空题.3分)用列举法写出集合A={y|y=x2-1.x∈Z.|x|≤1}=___5.(填空题.3分)已知不等式x2-ax+b≤0的解集为[2.3].则a+b=___6.(填空题.3分)命题“如果a≠0.那么a2>0”的逆否命题为___ .7.(填空题.3分)已知集合A={(x.y)|y=x+1.x∈R}.B={(x.y)|y=3-x.x∈R}.则A∩B=___ .8.(填空题.3分)若“x>1”是“x≥a”的充分不必要条件.则a的取值范围为___ .9.(填空题.3分)已知集合A={x||x-1|≤1}.B={x|ax=2}.若A∪B=A.则实数a的取值集合为___10.(填空题.3分)已知集合{x|(x-2)(x2-2x+a)=0.x∈R}中的所有元素之和为2.则实数a 的取值集合为___ .11.(填空题.3分)已知正实数x.y满足x+y=1.则1x - 4yy+1的最小值是___12.(填空题.3分)若不等式x+4 √3xy≤a(x+y)对任意x>0.y>0恒成立.则a的取值范围是___ .13.(单选题.3分)“x>1”是“ 1x<1”成立的()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14.(单选题.3分)若实数a、b满足条件a>b.则下列不等式一定成立的是()A. 1a <1bB.a2>b2C.ab>b2D.a3>b315.(单选题.3分)设集合P={m|-1<m≤0}.Q={m|mx2+2mx-1<0}对任意x∈R恒成立.则P与Q的关系是()A.P⊄QB.Q⊄PC.P=QD.P∩Q=∅16.(单选题.3分)已知集合A={1.2.3.…n)(n∈N*}.集合B={j1.j2.…j k)(k≥2.k∈N*)是集合A 的子集.若1≤j1<j2<…<j m≤n且j i+1-j i≥m(i=1.2.…….k-1).满足集合B的个数记为n(k⊕m).则7(3⊕2)=()A.9B.10C.11D.1217.(问答题.0分)已知x.y是实数.求证:x2+y2≥2x+2y-2..x∈R}.求A∩B.A∪18.(问答题.0分)已知全集U=R.集合A={x|x2-x-12<0}.B={y|y= x4+1x2(∁U B).19.(问答题.0分)已知命题p:关于x的一元二次方程x2-2 √3 x+|m-2|=0有两个不相等的实数根;命题q:关于x的一元二次方程x2-mx+|a+1|+|a-3|=0对于任意实数a都没有实数根.(1)若命题p为真命题.求实数m的取值范围;(2)若命题p和命题q中有且只有一个为真命题.求实数m的取值范围.20.(问答题.0分)已知集合A={x|x2-x-2≥0}.集合B={x|(1-m2)x2+2mx-1<0.m∈R}.(1)当m=2时.求集合∁R A和集合B;(2)若集合B∩Z为单元素集.求实数m的取值集合;(3)若集合(A∩B)∩Z的元素个数为n(n∈N*)个.求实数m的取值集合.21.(问答题.0分)已知集合P的元素个数为3n(n∈N*)个且元素为正整数.将集合P分成元素个数相同且两两没有公共元素的三个集合A、B、C.即P=A∪B∪C.A∩B=∅.A∩C=∅.B∩C=∅.其中A={a1.a2.….a n}.B={b1.b2.…b n}.C={c1.c2.….c n}.若集合A、B、C中的元素满足c1<c2<…<c n.a k+b k=c k.k=1.2.…n.则称集合P为“完美集合”.(1)若集合P={1.2.3}.Q={1.2.3.4.5.6}.判断集合P和集合Q是否为“完美集合”?并说明理由;(2)已知集合P={1.x.3.4.5.6}为“完美集合”.求正整数x的值;(3)设集合P={x|1≤x≤3n.n≥2.n∈N*}① 证明:集合P为“完美集合”的一个必要条件是n=4k或n=4k+1(k∈N*)② 判断当n=4时.集合P是否为“完美集合”.如果是.求出所有符合条件的集合C;如果不是.请说明理由.2018-2019学年上海市浦东新区建平中学高一(上)期中数学试卷参考答案与试题解析试题数:21.满分:01.(填空题.3分)设全集∪={1.2.3.4.5.6}.集合A={2.4.6}.则∁U A=___ .【正确答案】:[1]{1.3.5}【解析】:根据补集的定义写出∁U A.【解答】:解:全集∪={1.2.3.4.5.6}.集合A={2.4.6}.则∁U A={1.3.5}.故答案为:{1.3.5}.【点评】:本题考查了补集的定义与应用问题.是基础题.<0的解集是___ .2.(填空题.3分)不等式x−1x+2【正确答案】:[1](-2.1)【解析】:问题转化为(x-1)(x+2)<0.求出不等式的解集即可.<0.【解答】:解:∵ x−1x+2∴(x-1)(x+2)<0.解得:-2<x<1.故不等式的解集是(-2.1).故答案为:(-2.1).>0.再转化为整式不等式F(x)【点评】:解分式不等式的方法是:移项.通分化不等式为F(x)G(x)G(x)>0.然后利用二次不等式或高次不等式的结论求解.3.(填空题.3分)已知集合A={-1.0.2}.B={a2+1}.若B⊄A.则实数a的值为___ .【正确答案】:[1]a≠±1【解析】:先假设B⊂A.得a2+1=-1.a∈∅;a2+1=0.a∈∅;a2+1=2.a=±1;取补集得结果.【解答】:解:若B⊂A.则① a2+1=-1.a∈∅;② a2+1=0.a∈∅;③ a2+1=2.a=±1;∵B⊄A.∴a≠±1.故答案为:a≠±1.【点评】:本题考查的知识点集合的包含关系应用.难度不大.属于基础题.4.(填空题.3分)用列举法写出集合A={y|y=x2-1.x∈Z.|x|≤1}=___【正确答案】:[1]{-1.0}【解析】:由|x|≤1及x∈Z即可求出x=-1.0.或1.从而得出x2=0.或1.进而得出y的值.从而得出集合A.【解答】:解:∵|x|≤1.且x∈Z;∴x=-1.0.或1;∴x2=0.或1;∴y=-1.或0;∴A={-1.0}.故答案为:{-1.0}.【点评】:考查描述法、列举法的定义.以及绝对值不等式的解法.5.(填空题.3分)已知不等式x2-ax+b≤0的解集为[2.3].则a+b=___【正确答案】:[1]11【解析】:利用不等式与对应方程的关系.结合根与系数的关系求出a、b的值.【解答】:解:不等式x2-ax+b≤0的解集为[2.3].∴方程x2-ax+b=0的实数根为2和3.∴ {2+3=a.2×3=ba=5.b=6;∴a+b=11.故答案为:11.【点评】:本题考查了一元二次不等式与对应方程的关系应用问题.是基础题.6.(填空题.3分)命题“如果a≠0.那么a2>0”的逆否命题为___ .【正确答案】:[1]若a2≤0.则a=0【解析】:根据逆否命题的定义.即把结论和条件的否定后作为逆否命题的条件和结论即可.【解答】:解:原命题“如果a≠0.那么a2>0”.∴其逆否命题为:“若a2≤0.则a=0”.故答案为:若a2≤0.则a=0.【点评】:本题考查的知识点是逆否命题的定义.需要正确写出对条件的结论的否定.这是关键和易出错的地方.7.(填空题.3分)已知集合A={(x.y)|y=x+1.x∈R}.B={(x.y)|y=3-x.x∈R}.则A∩B=___ .【正确答案】:[1]{(1.2)}【解析】:根据交集定义得A∩B={(x.y)| {y=x+1y=3−x }=(1.2).【解答】:解:A∩B={(x.y)| {y=x+1y=3−x }={(1.2)}.故答案为:{(1.2)}.【点评】:此题考查了交集及其运算.需要注意此题是点集.是基础题.8.(填空题.3分)若“x>1”是“x≥a”的充分不必要条件.则a的取值范围为___ .【正确答案】:[1]a≤1【解析】:根据充分条件和必要条件的定义进行求解即可.【解答】:解:若“x>1”是“x≥a”的充分不必要条件.则a≤1.故答案为:a≤1【点评】:本题主要考查充分条件和必要条件的判断.比较基础.9.(填空题.3分)已知集合A={x||x-1|≤1}.B={x|ax=2}.若A∪B=A.则实数a的取值集合为___ 【正确答案】:[1][1.+∞)∪{0}.【解析】:分为B=∅.和B≠∅两种情况讨论.取并集得结论.【解答】:解:A={x|0≤x≤2}.① B=∅.a=0.② B≠∅.B={ 2a}.0<2a ≤2. a2≥ 12.∴a≥1.故实数a的取值集合为[1.+∞)∪{0}.故答案为:[1.+∞)∪{0}.【点评】:本题考查了集合的化简与集合的运算的应用.注意不要漏掉B=∅.属于基础题.10.(填空题.3分)已知集合{x|(x-2)(x2-2x+a)=0.x∈R}中的所有元素之和为2.则实数a 的取值集合为___ .【正确答案】:[1]{a|a=0或a>1}【解析】:推导出x2-2x+a=0的解为x=0或无解.由此能求出实数a的取值集合.【解答】:解:∵集合{x|(x-2)(x2-2x+a)=0.x∈R}中的所有元素之和为2.∴x2-2x+a=0的解为x=0或无解.∴a=0或△=4-4a<0.解得a>1.∴实数a的取值集合为{a|a=0或a>1}.故答案为:{a|a=0或a>1}.【点评】:本题考查实数的取值集合的求法.考查集合定义等基础知识.考查运算求解能力.是基础题.11.(填空题.3分)已知正实数x.y满足x+y=1.则1x - 4yy+1的最小值是___【正确答案】:[1] 12【解析】:由已知分离1x - 4yy+1= 1x−4y+4−4y+1= 1x+4y+1−4 .然后进行1的代换后利用基本不等式即可求解.【解答】:解:正实数x.y满足x+y=1.则1x - 4yy+1= 1x−4y+4−4y+1= 1x+4y+1−4= 12(1x+4y+1)[x+(y+1)]-4= 12 (5+y+1x +4x y+1 )-4 ≥12(5+4)−4 = 12当且仅当y+1x =4xy+1 且x+y=1即y= 13 .x= 23 时取得最小值是 12 /故答案为: 12【点评】:本题主要考查了利用基本不等式求解最值.解题的关键是进行分离后利用1的代换 12.(填空题.3分)若不等式x+4 √3xy ≤a (x+y )对任意x >0.y >0恒成立.则a 的取值范围是___ .【正确答案】:[1][4.+∞)【解析】:不等式x+4 √3xy ≤a (x+y ).x >0.y >0.a≥ x+4√3xy x+y=x y +4√3•x y x y+1 .令 √x y=t >0.可得:f(t )= t 2+4√3tt 2+1.利用导数研究其单调性极值最值即可得出.【解答】:解:∵不等式x+4 √3xy ≤a (x+y ).x >0.y >0. ∴a≥x+4√3xy x+y=x y +4√3•x y x y+1 .令 √x y=t >0.可得:f (t )=t 2+4√3tt 2+1. f′(t )= (2t+4√3)(t 2+1)−2t(t 2+4√3t)(t 2+1)2 = −4√3t 2+2t+4√3(t 2+1)2 = −(t+√32)(t−2√33)(t 2+1)2 . 可知:t=2√33时函数f (t )取得最大值. f (2√33) =4. f (0)=0. ∴0<f (t )≤4.∵不等式x+4 √3xy ≤a (x+y )对任意x >0.y >0恒成立. ∴a 的取值范围是a≥4. 故答案为:[4.+∞).【点评】:本题考查了利用导数研究函数的单调性极值与最值、等价转化方法、方程与不等式的解法.考查了推理能力与计算能力.属于难题. 13.(单选题.3分)“x >1”是“ 1x <1 ”成立的( ) 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【正确答案】:A【解析】:根据不等式的关系结合充分条件和必要条件的定义进行判断即可.【解答】:解:若x>1.则0<1x <1 .则1x<1成立.即充分性成立.若当x<0时. 1x<1成立.但x>1不成立.即必要性不成立.即“x>1”是“ 1x<1”成立的充分不必要条件.故选:A.【点评】:本题主要考查充分条件和必要条件的判断.根据不等式的性质结合充分条件和必要条件的定义是解决本题的关键.14.(单选题.3分)若实数a、b满足条件a>b.则下列不等式一定成立的是()A. 1a <1bB.a2>b2C.ab>b2D.a3>b3【正确答案】:D【解析】:根据题意.由不等式的性质依次分析选项.综合即可得答案.【解答】:解:根据题意.依次分析选项:对于A、a=1.b=-1时.有1a >1b成立.故A错误;对于B、a=1.b=-2时.有a2<b2成立.故B错误;对于C、a=1.b=-2时.有ab<b2成立.故C错误;对于D、由不等式的性质分析可得若a>b.必有a3>b3成立.则D正确;故选:D.【点评】:本题考查不等式的性质.对于错误的结论举出反例即可.15.(单选题.3分)设集合P={m|-1<m≤0}.Q={m|mx2+2mx-1<0}对任意x∈R恒成立.则P与Q的关系是()A.P⊄QB.Q⊄PC.P=QD.P∩Q=∅【正确答案】:C【解析】:先分别求出集合P.Q.由此能求出P与Q的关系.【解答】:解:∵集合P={m|-1<m≤0}.Q={m|mx2+2mx-1<0}对任意x∈R恒成立.∴Q={m|-1<m≤0}.∴P与Q的关系是P=Q.故选:C.【点评】:本题考查集合的关系的判断.考查不等式性质等基础知识.考查运算求解能力.是基础题.16.(单选题.3分)已知集合A={1.2.3.…n)(n∈N*}.集合B={j1.j2.…j k)(k≥2.k∈N*)是集合A 的子集.若1≤j1<j2<…<j m≤n且j i+1-j i≥m(i=1.2.…….k-1).满足集合B的个数记为n(k⊕m).则7(3⊕2)=()A.9B.10C.11D.12【正确答案】:B【解析】:根据n(k⊕m)和7(3⊕2).可得n=7.k=3.m=2.集合A={1.2.3.4.5.6.7};集合B={j1.j2.j3}.1≤j1<j2≤7满足集合B的个数列罗出来.可得答案.【解答】:解:由题意可得n=7.k=3.m=2.那么集合A={1.2.3.4.5.6.7};集合B={j1.j2.j3}.1≤j1<j2≤7.j i+1-j i≥2满足集合B的个数列罗出来.可得:{1.3.5}.{1.3.6}.{1.3.7}.{1.4.6}.{1.4.7};{1.5.7}.{2.4.6}.{2.4.7}.{2.5.7}.{3.5.7}.故选:B.【点评】:本题考查子集与真子集.并且即时定义新的集合.主要考查学生的阅读理解能力.17.(问答题.0分)已知x.y是实数.求证:x2+y2≥2x+2y-2.【正确答案】:【解析】:利用综合法.证明不等式即可.【解答】:证明:因为x2-2x+1=(x-1)2≥0.可得x2≥2x-1.y2-2y+1=(y-1)2≥0.可得y2≥2y-1.所以x2+y2≥2x+2y-2.【点评】:本题考查不等式的证明.综合法的应用.是基本知识的考查.18.(问答题.0分)已知全集U=R.集合A={x|x2-x-12<0}.B={y|y= x4+1.x∈R}.求A∩B.A∪x2(∁U B).【正确答案】:【解析】:先求出A.B.然后进行交集、并集和补集的运算即可.【解答】:解:A={x|-3<x<4};∵x4+1≥2x2;∴ x4+1≥2;x2∴B={y|y≥2};∴A∩B=[2.4).∁U B={y|y<2};∴A∪(∁U B)=(-∞.4).【点评】:考查描述法表示集合的定义.a2+b2≥2ab.以及交集、并集和补集的运算.19.(问答题.0分)已知命题p:关于x的一元二次方程x2-2 √3 x+|m-2|=0有两个不相等的实数根;命题q:关于x的一元二次方程x2-mx+|a+1|+|a-3|=0对于任意实数a都没有实数根.(1)若命题p为真命题.求实数m的取值范围;(2)若命题p和命题q中有且只有一个为真命题.求实数m的取值范围.【正确答案】:【解析】:(1)由题意可得判别式大于0.由绝对值不等式的解法可得m 的范围;(2)考虑命题q 真.运用绝对值不等式的性质和判别式小于0.解不等式可得m 的范围.由p.q 一真一假.解不等式即可得到所求范围.【解答】:解:(1)命题p :关于x 的一元二次方程x 2-2 √3 x+|m-2|=0有两个不相等的实数根.可得△=12-4|m-2|>0.解得-1<m <5;(2)命题q :关于x 的一元二次方程x 2-mx+|a+1|+|a-3|=0对于任意实数a 都没有实数根. 可得-x 2+mx=|a+1|+|a-3|.由|a+1|+|a-3|≥|a+1-a+3|=4.可得-x 2+mx-4≥0无实数解.可得△=m 2-16<0.即-4<m <4.命题p 和命题q 中有且只有一个为真命题.可得 {−1<m <5m ≥4或m ≤−4 或 {m ≥5或m ≤−1−4<m <4. 即有4≤m <5或-4<m≤-1.【点评】:本题考查二次方程和二次不等式的解法.注意运用判别式和绝对值不等式的性质.考查化简运算能力.属于基础题.20.(问答题.0分)已知集合A={x|x 2-x-2≥0}.集合B={x|(1-m 2)x 2+2mx-1<0.m∈R}.(1)当m=2时.求集合∁R A 和集合B ;(2)若集合B∩Z 为单元素集.求实数m 的取值集合;(3)若集合(A∩B )∩Z 的元素个数为n (n∈N *)个.求实数m 的取值集合.【正确答案】:【解析】:(1)m=2时.化简集合A.B.即可得集合∁R A 和集合B ;(2)集合B∩Z 为单元素集.所以集合B 中有且只有一个整数.而0∈B .所以抛物线y=(1-m 2)x 2+2mx-1的开口向上.且与x 轴的两个交点都在[-1.1]内.据此列式可得m=0;(3)集合(A∩B )∩Z 的元素个数为n (n∈N *)个.等价于(1-m 2)x 2+2mx-1<0在(-∞.-1]∪[2.+∞)上有整数解.【解答】:解:集合A={x|x 2-x-2≥0}={x|x≥2或x≤-1}.集合{x|(1-m 2)x 2+2mx-1<0.m∈R}={x|[(1+m )x-1][(1-m )x+1]<0}(1)当m=2时.集合∁R A={x|-1<x <2};集合B={x|x >1或x < 13 };(2)因为集合B∩Z 为单元素集.且0∈B .所以 {(1−m 2)×(−1)2−2m −1≥0(1−m 2)×12+2m −1≥0.解得m=0. 当m=0时.经验证.满足题意.故实数m 的取值集合为{0}(3)集合(A∩B )∩Z 的元素个数为n (n∈N *)个.等价于(1-m 2)x 2+2mx-1<0在(-∞.-1]∪[2.+∞)上有整数解.所以令f (x )=(1-m 2)x 2+2mx-1.依题意有1-m 2≤0或 {1−m 2>0f (−1)<0 或 {1−m 2>0f (2)<0 . 解得m <- 12或m >0.【点评】:本题考查了交、并、补集的混合运算.属难题.21.(问答题.0分)已知集合P 的元素个数为3n (n∈N *)个且元素为正整数.将集合P 分成元素个数相同且两两没有公共元素的三个集合A 、B 、C.即P=A∪B∪C .A∩B=∅.A∩C=∅.B∩C=∅.其中A={a 1.a 2.….a n }.B={b 1.b 2.…b n }.C={c 1.c 2.….c n }.若集合A 、B 、C 中的元素满足c 1<c 2<…<c n .a k +b k =c k .k=1.2.…n .则称集合P 为“完美集合”.(1)若集合P={1.2.3}.Q={1.2.3.4.5.6}.判断集合P 和集合Q 是否为“完美集合”?并说明理由;(2)已知集合P={1.x.3.4.5.6}为“完美集合”.求正整数x 的值;(3)设集合P={x|1≤x≤3n .n≥2.n∈N *}① 证明:集合P 为“完美集合”的一个必要条件是n=4k 或n=4k+1(k∈N *)② 判断当n=4时.集合P 是否为“完美集合”.如果是.求出所有符合条件的集合C ;如果不是.请说明理由.【正确答案】:【解析】:(1)根据完美集合的定义.将P 分为集合{1}、{2}、{3}符合条件.将Q 分成3个.每个中有两个元素.根据完美集合的定义进一步判断即可;(2)根据完美集合的概念直接求出集合C.从而得到x 的值;(3) ① P 中所有元素之和为 3n (3n+1)2 =2(c 1+c 2+…+c n-1+c n ).根据 9n (n−1)4=c 1+c 2+…+c n-1.等号右边为正整数.可得等式左边9n (n-1)可以被4整除.从而证明结论; ② 根据p 是完美集合.直接列出集合A.B.C 即可.【解答】:解:(1)将P 分为集合{1}、{2}、{3}.满足条件.是完美集合.将Q 分成3个.每个中有两个元素.若为完美集合.则a 1+b 1=c 1 、a 2+b 2=c 2.Q 中所有元素之和为21.21÷2=c 1+c 2=10.5.不符合要求;(2)若集合A={1.4}.B={3.5}.根据完美集合的概念知集合C={6.7}.若集合A={1.5}.B={3.6}.根据完并集合的概念知集合C={4.11}.若集合A={1.3}.B={4.6}.根据完并集合的概念知集合C={5.9}.故x 的一个可能值为7.9.11 中任一个;(3) ① 证明:P 中所有元素之和为1+2+…+3n= 3n (3n+1)2=a 1+b 1+c 1+a 2+b 2+c 2+…+a n +b n +c n =2(c 1+c 2+…+c n-1+c n ).∵c n =3n.∴3n (3n+1)4 =c 1+c 2+…+c n-1+3n. ∴ 9n (n−1)4=c 1+c 2+…+c n-1.等号右边为正整数. 则等式左边9n (n-1)可以被4整除.∴n=4k 或n-1=4k.即n=4k 或n=4k+1;② p 是完美集合.A={1.4.3.2}.B={6.5.8.10}.C={7.9.11.12}或A={1.2.4.3}.B={5.8.7.9}.C={6.10.11.12}或A={2.4.3.1}.B={6.5.7.11}.C={8.9.10.12}.【点评】:本题考查了集合的交、并、补集的混合运算和等差数列的前n 项和.考查了分类讨论思想和计算能力.属难题.。
上海市建平中学2018-2019学年上学期高三期中数学模拟题 班级__________ 座号_____ 姓名__________ 分数__________一、选择题(本大题共12小题,每小题5分,共60分.每小题给出的四个选项中,只有一项是符合题目要求的.)1. 若集合,则= ( )ABC D2. 若{}n a 为等差数列,n S 为其前项和,若10a >,0d <,48S S =,则0n S >成立的最大自 然数为( )A .11B .12C .13D .14 3. 设a ,b ∈R ,i 为虚数单位,若2+a i1+i =3+b i ,则a -b 为( )A .3B .2C .1D .04. 已知集合A={x ∈Z|(x+1)(x ﹣2)≤0},B={x|﹣2<x <2},则A ∩B=( ) A .{x|﹣1≤x <2} B .{﹣1,0,1} C .{0,1,2}D .{﹣1,1}5. 已知实数[1,1]x ∈-,[0,2]y ∈,则点(,)P x y 落在区域20210220x y x y x y +-⎧⎪-+⎨⎪-+⎩……… 内的概率为( )A.34B.38C.14D.18【命题意图】本题考查线性规划、几何概型等基础知识,意在考查数形结合思想及基本运算能力. 6. 已知全集为R ,且集合}2)1(log |{2<+=x x A ,}012|{≥--=x x x B ,则)(B C A R 等于( ) A .)1,1(- B .]1,1(- C .)2,1[ D .]2,1[【命题意图】本题考查集合的交集、补集运算,同时也考查了简单对数不等式、分式不等式的解法及数形结合的思想方法,属于容易题.7. 设函数()y f x =对一切实数x 都满足(3)(3)f x f x +=-,且方程()0f x =恰有6个不同的实根,则这6个实根的和为( )A.18B.12C.9D.0【命题意图】本题考查抽象函数的对称性与函数和方程等基础知识,意在考查运算求解能力.8. 已知2,0()2, 0ax x x f x x x ⎧+>=⎨-≤⎩,若不等式(2)()f x f x -≥对一切x R ∈恒成立,则a 的最大值为( )A .716-B .916-C .12-D .14-9. 函数()2cos()f x x ωϕ=+(0ω>,0ϕ-π<<)的部分图象如右图所示,则 f (0)的值为( ) A.32-B.1-C.D.【命题意图】本题考查诱导公式,三角函数的图象和性质,数形结合思想的灵活应用. 10.已知角α的终边经过点(sin15,cos15)-,则2cos α的值为( )A.12+B.12 C. 34 D .0 11.已知,,a b c 为ABC ∆的三个角,,A B C 所对的边,若3cos (13cos )b C c B =-,则sin :sin C A =( )A .2︰3B .4︰3C .3︰1D .3︰2 【命题意图】本题考查正弦定理、余弦定理,意在考查转化能力、运算求解能力.12.已知实数y x ,满足不等式组⎪⎩⎪⎨⎧≤-≥+≤-5342y x y x x y ,若目标函数mx y z -=取得最大值时有唯一的最优解)3,1(,则实数m 的取值范围是( )A .1-<mB .10<<mC .1>mD .1≥m【命题意图】本题考查了线性规划知识,突出了对线性目标函数在给定可行域上最值的探讨,该题属于逆向问题,重点把握好作图的准确性及几何意义的转化,难度中等.二、填空题(本大题共4小题,每小题5分,共20分.把答案填写在横线上)13.若函数63e ()()32ex x bf x x a =-∈R 为奇函数,则ab =___________. 【命题意图】本题考查函数的奇偶性,意在考查方程思想与计算能力.14.在ABC ∆中,角A B C 、、的对边分别为a b c 、、,若1cos 2c B a b ⋅=+,ABC ∆的面积12S c =, 则边c 的最小值为_______.【命题意图】本题考查正弦定理、余弦定理、三角形面积公式、基本不等式等基础知识,意在考查基本运算能力.15.已知,0()1,0x e x f x x ì³ï=í<ïî,则不等式2(2)()f x f x ->的解集为________.【命题意图】本题考查分段函数、一元二次不等式等基础知识,意在考查分类讨论思想和基本运算能力. 16.三角形ABC中,2,60AB BC C ==∠=,则三角形ABC 的面积为 .三、解答题(本大共6小题,共70分。
建平中学高三上期中测试试卷一. 填空题1. 函数2()log (3)f x x =-的定义域是2. 若集合1{|0}3x A x x -=>-,则R C A = 3. 函数()sin f x x =的零点是4. 已知θ是第二象限角且4cos 5θ=-,则sin()4πθ+= 5. 在扇形OAB 中,中心角23AOB π∠=,若弧AB 的长为2π,则扇形OAB 的面积为 6. 函数sin(2)4y x π=+的单调递增区间为7. 函数2()2cos sin 21f x x x =+-,[0,]2x π∈的值域为 8. 函数()sin f x A x ω=(0A >,0ω>)在[0,]π上至少取到一次振幅,则频率的最小 值为9. 已知函数()f x 满足:对任意,a b R ∈,a b ≠,都有()()()()af a bf b af b bf a +>+,则不等式(||)(21)f x f x >+的解集为10. 若关于x 的不等式2cos 40x ax x π-+≥对任意*x N ∈成立,则实数a 的取值范围是11. 设函数()f x 、()g x 的定义域均为R ,若对任意12,x x R ∈,且12x x <,具有12()()f x f x ≤,则称函数()f x 为R 上的单调非减函数,给出以下命题:① 若()f x 关于点(,0)a 和直线x b =(b a ≠)对称,则()f x 为周期函数,且2()b a -是 ()f x 的一个周期;② 若()f x 是周期函数,且关于直线x a =对称,则()f x 必关于无穷多条直线对称;③ 若()f x 是单调非减函数,且关于无穷多个点中心对称,则()f x 的图像是一条直线; ④ 若()f x 是单调非减函数,且关于无穷多条平行于y 轴的直线对称,则()f x 是常值函数; 以上命题中,所有真命题的序号是12. 已知1a 、2a 、3a 、4a 与1b 、2b 、3b 、4b 是8个不同的实数,若方程12341234||||||||||||||||x a x a x a x a x b x b x b x b -+-+-+-=-+-+-+-有有限多个解,则此方程的解最多有 个二. 选择题13. 将函数sin 2y x =的图像向左平移4π个单位,得到函数( )的图像 A. sin 2y x = B. cos2y x = C. sin 2y x =- D. cos2y x =- 14. 下列函数在其定义域上既是奇函数,又是增函数的是( )A. lg(y x =B. 1lg1x y x +=- C. 11212x y =+- D. 1122x x y +-+=- 15. 下列关于充分必要条件的判断中,错误的是( )A. “(0,)2x π∈”是“1sin 2sin x x+≥”的充分条件 B. “2a b +≥”是“1ab ≥”的必要条件C. “0x >”是“12x x+≥”的充要条件D. “0a >,0b >”是“a b +> 16. 汽车的“燃油效率”是指汽车每消耗1升汽油行使的里程,下图描述了甲、乙、丙三辆汽车在不同速度下的燃油效率情况,下列叙述中正确的是( )A. 消耗1升汽油,乙车最多可行使5千米B. 以相同速度行使相同路程,三辆车中,甲车消耗汽油最多C. 甲车以80千米/小时的速度行使1小时,消耗10升汽油D. 某城市机动车最高限速80千米/小时,相同条件下,在该市用丙车比用乙车更省油三. 解答题17. 在ABC ∆中,角A 、B 、C 所对的边分别为a 、b 、c ,1cos 3A =.(1)若cos B =,求a b的值;(2)若a =ABC ∆的面积的最大值.18. 设函数()41x f x =-(0x ≥)的反函数为1()f x -,4()log (31)g x x =+.(1)求1()f x -;(2)若函数1()2()()h x g x f x -=-的图像与直线y a =有公共点,求实数a 的取值范围.19. 某工程队共有500人,要建造一段6000米的高速公路,工程需要把500人分成两组,甲组的任务是完成一段4000米的软土地带,乙组的任务是完成剩下的2000米的硬土地带,据测算,软、硬土地每米的工程量是30工(工为计量单位)和40工.(1)若平均分配两组的人数,分别计算两组完工的时间,并求出此时全队的筑路工期;(2)如何分配两组的人数会使得全队的筑路工期最短?20. 已知函数()||f x x x a bx =-+,,a b R ∈.(1)若0a =,判断()f x 的奇偶性,并说明理由;(2)若0b =,求()f x 在[1,3]上的最小值;(3)若0b >,且22()3a b f x +=有三个不同实根,求22ab a b +的取值范围.21. 给定函数()f x 、()g x ,定义()()()((),())()()()f x f x g x F f x g x g x f x g x ≥⎧=⎨<⎩. (1)证明:()()|()()|((),())2f xg x f x g x F f x g x ++-=; (2)若()sin2cos f x x x =-,()sin 2cos g x x x =+,证明:((),())F f x g x 是周期函数;(3)若11()sin f x A x ω=,22()sin g x A x ω=,0i A ≠,0i ω≠,1,2i =,证明:()()f x g x +是周期函数的充要条件是21ωω为有理数.参考答案一. 填空题1. (3,)+∞2. [1,3]3. {|,}x x k k Z π=∈4. 10-5. 3π6. 3[,]88k k ππππ-+,k Z ∈7. [- 8. 14π 9. 1(,)3-∞- 10. 13[,4]3- 11. ②④ 12. 4二. 选择题13. B 14. D 15. B 16. D三. 解答题17.(1)2;(218.(1)14()log (1)f x x -=+(0x ≥);(2)0a ≥. 19.(1)硬土480,软土320,全队工期480;(2)硬土300人,软土200人.20.(1)奇函数;(2)min 11013()393414a a a f x a a a a -<⎧⎪≤≤⎪=⎨-<<⎪⎪-≥⎩;(3)11(,)63. 21. 略.。
上海市建平中学2018届高三上学期期中考试数学试题2017.11一.填空题1. 函数f (x) Tog2(x—3)的定义域是 ___________x _12. 若集合A ={x| 0},则C R A二 ________x_33. 函数f (x)二sinx的零点是_________4 J!4. 已知二是第二象限角且cos ,则sin(二-')二__________5 42 1T5. 在扇形OAB中,中心角• AOB二幺,若弧AB的长为2二,则扇形OAB的面积为36. 函数y =sin(2x ')的单调递增区间为______________47. 函数f(x) =2cos2x sin2 x -1,x • [0「]的值域为___________28. 函数f(x) =As in •‘X ( A .0,u >0 )在[0,二]上至少取到一次振幅,则频率的最小值为_________9. 已知函数f (x)满足:对任意a,b R,a中b,都有af (a) bf (b) af (b) bf (a),则不等式f(|x|) ■ f(2x 1)的解集为______________Q *10. 若关于x的不等式x -axcos二x・4一0对任意N成立,则实数a的取值范围是11. 设函数f (x)、g(x)的定义域均为R,若对任意x1,x^ R,且x1:::x2,具有f (x1^l f (x2),则称函数f (x)为R上的单调非减函数,给出以下命题:①若f(x)关于点(a,0)和直线x=b( b=a)对称,则f (x)为周期函数,且2(b - a)是f(x)的一个周期;②若f(x)是周期函数,且关于直线X二a对称,则f(x)必关于无穷多条直线对称;③若f(x)是单调非减函数,且关于无穷多个点中心对称,则f(x)的图像是一条直线;④若f(x)是单调非减函数,且关于无穷多条平行于y轴的直线对称,则f (x)是常值函数;以上命题中,所有真命题的序号是___________12. 已知a1、a2、a3、a°与d、b?、R、是8个不同的实数,若方程|x—a1||x—a2||x—a3||x—a4|=|x—b1||x—b2||x— b3「|x — b4| 有有限多个解,则此方程的解最多有_________ 个3选择题13.将函数y =sin2x 的图像向左平移 二个单位,得到函数()的图像4A. y =sin2xB. y=cos2xC. y =—sin 2xD. y = —cos2x14. 下列函数在其定义域上既是奇函数,又是增函数的是(15.下列关于充分必要条件的判断中,错误的是()A. “ x • (0,二)”是“ sinx • — - 2 ”的充分条件2sin xB. “ a b _2 ”是“ ab _1 ”的必要条件 1C. “ x 0 ”是“ X • — _ 2 ”的充要条件xD. “ a 0, b • 0 ”是“ a b 2一 ab ”的非充分非必要条件16. 汽车的“燃油效率”是指汽车每消耗 1升汽油行使的里程,下图描述了甲、乙、丙三辆 汽车在不同速度下的燃油效率情况,下列叙述中正确的是()A. 消耗1升汽油,乙车最多可行使5千米B. 以相同速度行使相同路程,三辆车中, 甲车消耗汽油最多C. 甲车以80千米/小时的速度行使1小时, 消耗10升汽油D. 某城市机动车最高限速 80千米/小时, 相同条件下,在该市用丙车比用乙车更省油三.解答题(1) 若cosB讨,求b 的值;(2) 若a =讦3,求 ABC 的面积的最大值A. y = lg(x . x -1)B.C.y =7^7 22-12D. y =2x1-2"17.在 ABC 中,角A 、B 、C 所对的边分别为 cos A 二VHHI F ,1x 118.设函数 f(x)=4 -1 ( x_0 )的反函数为 f —(x), g(x^log 4(3x 1). (1 )求 f "(x);(2)若函数h(x) =2g(x) - f 」(x)的图像与直线y =a 有公共点,求实数 a 的取值范围19.某工程队共有500人,要建造一段6000米的高速公路,工程需要把 500人分成两组, 甲组的任务是完成一段 4000米的软土地带,乙组的任务是完成剩下的 2000米的硬土地带, 据测算,软、硬土地每米的工程量是 30工(工为计量单位)和 40工.(1 )若平均分配两组的人数,分别计算两组完工的时间,并求出此时全队的筑路工期; (2 )如何分配两组的人数会使得全队的筑路工期最短?20.已知函数 f (x) = x | x 「a | bx , a,b R .(1 )若a=0,判断f (x)的奇偶性,并说明理由; (2 )若b=0,求f(x)在[1,3]上的最小值;f (x) f (x) - g(x) 21.给定函数 f(x)、g(x),定义 F(f(x),g(x)) .l g(x) f(x)<g(x)/、"口f (x)+g(x) + | f (x)—g(x) |(1)证明:F(f(x),g(x)):(2 )若 f(x) =si n2x-cosx , g(x) =si n2x cosx ,证明:F (f (x), g(x))是周期函数; (3)若 f(x)=A t Si n “X ,in 2x , A=0,- - 0 , i =1,2,证明:f (x) • g(x)是周期函数的充要条件是为有理数.(3)若 b0, 且 f(x)二a 2b 2有三个不同实根,十的取值范围.填空题三.解答题精美句子1、善思则能“从无字句处读书”。
读沙漠,读出了它坦荡豪放的胸怀;读太阳,读出 了它普照万物的无私;读春雨,读出了它润物无声的柔情。
读大海,读出了它气势磅礴 的豪情。
读石灰,读出了它粉身碎骨不变色的清白。
2、幸福幸福是“临行密密缝,意恐迟迟归”的牵挂;幸福是“春种一粒粟,秋收千颗子”的收获.幸福是“采菊东篱下,悠然见南山”的闲适;幸福是“奇闻共欣赏, 疑义相与析”的愉悦。
幸福是“随风潜入夜,润物细无声”的奉献;幸福是“夜来风雨 声,花落知多少”的恬淡。
幸福是“零落成泥碾作尘,只有香如故”的圣洁。
幸福是“壮 志饥餐胡虏肉,笑参考答案1. (3, ::)2. [1,3]3. {x | x 二 k 二,k Z}4.2 105. 3二3兀兀,-6. [k ,k ], k Z 8 810. [-£,4]11.②④7. [-1八2]8.19.(-二)二.选择题 13. B14. D 15. B 16. D17. (1) 2; (2)3;24 18. (1)1f (x) =log 4(x+1) ( xX0 ); (2) aX0.19. (1)硬土 480,软土 320,全队工期 480; (2)硬土 300 人,软土 200 人.20. (1)奇函数;21. 略.(2) f (x)min"1-aac10 r 1Ea 兰3 ‘3a -9 3ca c4 i a —1 a 启41 1;(3)(1?谈渴饮匈奴血”的豪壮。
幸福是“先天下之忧而忧,后天下之乐而乐” 的胸怀。
幸福是“人生自古谁无死,留取丹心照汗青”的气节。
3、大自然的语言丰富多彩:从秋叶的飘零中,我们读出了季节的变换;从归雁的行列中,我读出了集体的力量;从冰雪的消融中,我们读出了春天的脚步;从穿石的滴水中,我们读出了坚持的可贵;从蜂蜜的浓香中,我们读出了勤劳的甜美。
4、成功与失败种子,如果害怕埋没,那它永远不能发芽。
鲜花,如果害怕凋谢,那它永远不能开放。
矿石,如果害怕焚烧(熔炉),那它永远不能成钢(炼成金子)。
蜡烛,如果害怕熄灭(燃烧),那它永远不能发光。
航船,如果害怕风浪,那它永远不能到达彼岸。
5、墙角的花,当你孤芳自赏时,天地便小了。
井底的蛙,当你自我欢唱时,视野便窄了。
笼中的鸟,当你安于供养时,自由便没了。
山中的石!当你背靠群峰时,意志就坚了。
水中的萍!当你随波逐流后,根基就没了。
空中的鸟!当你展翅蓝天中,宇宙就大了。
空中的雁!当你离开队伍时,危险就大了。
地下的煤!你燃烧自己后,贡献就大了6、朋友是什么?朋友是快乐日子里的一把吉它,尽情地为你弹奏生活的愉悦;朋友是忧伤日子里的一股春风,轻轻地为你拂去心中的愁云。
朋友是成功道路上的一位良师,热情的将你引向阳光的地带;朋友是失败苦闷中的一盏明灯,默默地为你驱赶心灵的阴霾。
7、一粒种子,可以无声无息地在泥土里腐烂掉,也可以长成参天的大树。
一块铀块,可以平庸无奇地在石头里沉睡下去,也可以产生惊天动地的力量。
一个人,可以碌碌无为地在世上厮混日子,也可以让生命发出耀眼的光芒。
8、青春是一首歌,她拨动着我们年轻的心弦;青春是一团火,她点燃了我们沸腾的热血;青春是一面旗帜,她召唤着我们勇敢前行;青春是一本教科书,她启迪着我们的智慧和心灵。