江西师范大学附属中学2017届高三3月月考英语试卷
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湖南省长沙市湖南师大附中2025届高三月考试卷(三)语文试题本试卷共四道大题,23道小题,满分150分。
时量150分钟。
得分:_一、现代文阅读(35分)(一)现代文阅读I(本题共5小题,19分)阅读下面的文字,完成1~5题。
对于大部分人来说,隐喻不是寻常的语言,而是诗意的想象和修辞多样性的一种策略,非同寻常。
而且,隐喻通常被看成语言文字的特征,而非思想和行为的特点。
由于这个原因,大多数人认为没有隐喻的存在,他们依然可以自如地生活,而我们发现事实恰恰相反。
不论是在语言上还是在思想和行动中,日常生活中隐喻无所不在,我们思想和行为所依据的概念系统本身是以隐喻为基础。
这些支配着我们思想的概念不仅关乎我们的思维能力,它们也同时管辖我们日常的运作,乃至一些细枝末叶的平凡细节。
这些概念建构了我们的感知,构成了我们如何在这个世界生存以及我们与其他人的关系。
因此,我们的这个概念系统在界定日常现实中扮演着举足轻重的角色。
我们的概念系统大部分是隐喻——如果我们说的没错的话,那么我们的思维方式,我们每天所经历所做的一切就充满了隐喻。
但是我们的概念系统不是我们平时能够意识到的。
我们每天所做的大部分琐事都只是按照某些方式或多或少地在自动思维和行动。
这些方式是什么却并非显而易见。
要搞清这些,一个方法就是研究语言。
既然交流是基于我们用以思考和行动的同一个概念系统,那么语言就是探明这个系统是什么样子的重要证据来源。
基于语言学证据(linguistic evidence),我们已经发现我们普通的概念系统,究其实质,大都是隐喻的,并且找到了一种方式来仔细鉴定那些建构我们如何感知、如何思考、如何行动的隐喻究竟是什么。
为了说明什么样的概念是隐喻,这样的概念又如何建构我们的日常活动,让我们从“争论”(ARGUMENT)以及“争论是战争”这个概念隐喻开始阐述吧。
日常生活中总是能见到这类表达:争论是战争你的观点无法防御。
他攻击我观点中的每一个弱点。
江科附中2024-2025学年第一学期高一年级10月月考英语试卷卷面分数:150分考试时间:120分钟第一部分听力第一节(共两节,满分30分)听下面5段对话。
每段对话后有一个小题,从题中所给的ABC三个选项中选出最佳选项。
听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。
每段对话仅读一遍。
1.What will the woman probably do?A.Clean the house.B.Cut the grass.C.Wash the cars.2.What food would the boy like to eat now?A.Cake.B.Eggs.C.Beef.3.How long have the people been waiting in the cold?A.All morning.B.All night.C.One day.4.When should the woman feed her cat?A.When the cat wakes up.B.After the cat plays for an hour.C.Before she goes to sleep.5.Where is the man?A.On a bus.B.In a taxi.C.On the subway.第二节听5段对话或独白,每段对话或独白后有几个小题,从题中所给ABC三个选项中选出最佳选项,听每段对话或独白前,你有时间阅读各个小题,每小题5秒钟;听完后各小题将给出5秒钟的作答时间,每段对话或独白读遍。
听第6段材料,回答第6、7题。
6.What is Tom doing?A.Organizing his equipment.B.Fishing with his family.C.Playing on the riverside.7.Who made Tom become interested in fishing?A.His best friend.B.His brother.C.His father.听第7段材料,回答第8至10题。
第一次月考一、单选题1. 等差数列{}n a 中,1239a a a ++=,4516a a +=,则6a =( ) A. 9 B. 10 C. 11 D. 12【答案】C【解析】因为1231339a a a a d ++=+=,4512716+=+=a a a d , 所以可解得1a 1,d 2,所以61511011a a d =+=+=,故选:C2.在正项等比数列{}n a 中,n S 为其前n 项和,若1010S =,2030S =,则30S 的值为( ) A .50 B .70 C .90 D .110【答案】B【解析】由等比数列的片段和性质得10S ,1200S S −,3020S S −成等比数列 所以()()22010103020S S S S S −=− 所以()()23030101030S −=−, 解得3070S =. 故选:B.3.用数学归纳法证明“1111112331n n n n ++++>++++”时,假设n k =时命题成立,则当1n k =+时,左端增加的项为( ) A .134k + B .11341k k −++ C .111323334k k k +++++ D .11232343(1)k k k +−+++ 131k +++111+31323k k k ++++111+31331111233123k k k k k k k ⎫++−⎪+++⎭⎫+++⎪++++⎭故选:D4.已知数列{}n a 为等差数列,首项10a >,若101210131a a <−,则使得0n S >的n 的最大值为( ) A .2022 B .2023C .2024D .20255. 已知数列{}n a 为正项递增等比数列,123212a a a ++=,12311176a a a ++=,则该等比数列的公比q =( )A. 2B. 3C. 4D. 5【答案】A【解析】由题意10,1a q >>, 由123212a a a ++=,1312321231322111716a a a a a a a a a a a a +++++==+=, 得2221726a =,所以23a =(23a =−舍去),所以132********q a a q =−=++=, 整理得22520q q −+=,解得2q (12q =舍去), 所以2q.故选:A.6.近几年,我国在电动汽车领域有了长足的发展,电动汽车的核心技术是动力总成,而动力总成的核心技术是电机和控制器,我国永磁电机的技术已处于国际领先水平.某公司计划今年年初用196万元引进一条永磁电机生产线,第一年需要安装、人工等费用24万元,从第二年起,包括人工、维修等费用每年所需费用比上一年增加8万元,该生产线每年年产值保持在100万元.则引进该生产线后总盈利的最大值为( ) A .204万元 B .220万元C .304万元D .320万元7. 已知数列{}n a 的前n 项和为n S ,且满足12cos 3n n n a a a ++++=,11a =,则2023S =( ) A. 0 B.12C. lD. 32【答案】C【解析】解:()()()20231234567202120222023S a a a a a a a a a a =++++++++++2π5π1coscos 33=++++2018π2021πcoscos33+ 2π5π1337cos cos 133⎛⎫=+⨯+= ⎪⎝⎭.故选:C .8.已知数列{}n a 的前n 项和为n S ,数列{}n b 的前n 项和为n T ,且111,1,1n n n n a S n a b a +=+==+,则使得n T M <恒成立的实数M 的最小值为( )A .1B .32C .76D .2【答案】C【解析】数列{}n a 中,11a =,1n n a S n +=+,当2n ≥时,11n n a S n −=+−,两式相减得11n n n a a a +−=+,二、多选题9.在等比数列{}n a 中,11a =,427a =,则( ) A .{}1n n a a +的公比为9 B .{}31log n a +的前20项和为210C .{}n a 的前20项积为2003D .()111()231nn k k k a a −+=+=−∑2020++=,n a 的前201919033⨯⨯=,因为()1313n n a −++}1n n a a ++的前)13213n −=−10.下列命题中正确的是( )A .已知随机变量16,3XB ⎛⎫⎪⎝⎭,则()3212D X += B .若随机事件A ,B 满足:()12P A =,()23P B =,()56P A B ⋃=,则事件A 与B 相互独立C .若事件A 与B 相互独立,且()()01P A P B <<,则()()P A B P A =D .若残差平方和越大,则回归模型对一组数据()11,x y ,()22,x y ,…,(),n n x y 的拟合效果越好11. 已知数列1C :0,2,0,2,0,现在对该数列进行一种变换,规则f :每个0都变为“2,0,2”,每个2都变为“0,2,0”,得到一个新数列,记数列()1k k C f C +=,1,2,3,k =,且n C 的所有项的和为n S ,则以下判断正确的是( )A. n C 的项数为153n −⋅B. 4136S =C. 5C 中0的个数为203D. 1531n n S −=⋅−【答案】ABC【解析】设数列{}n C 的项数为一个数列{}n a ,因为1C 中有5项,即15a =, 根据题意:在f 作用下,每个0都变为“2,0,2”,每个2都变为“0,2,0”, 所以有()13Nn n a a n *+=∈,由此可知数列{}n a 为首相15a =,公比3q =的等比数列, 所以n C 的项数为153n n a −=⋅,故A 正确;根据变换规则,若数列的各项中,2与0的个数相同, 则与之相邻的下一个数列中2与0的个数也相同;若2比0多n 个,则与之相邻的下一个数列中2比0的个数少n 个, 若2比0少n 个,则与之相邻的下一个数列中2比0的个数多n 个,因为1C 中有5项,其中2个2,3个0,2比0少1个, 所以2C 的15项中,2比0的个数多1个,以此类推,若n 为奇数,则数列的各项中2比0少1个, 若n 为偶数,则数列的各项中2比0多1个,4C 中4n =,项数为353135⋅=个,n 为偶数,所以2的个数为1351682+=, 所以4682136S =⨯=,所以B 正确;5C 中共有453405⋅=项,其中5n =为奇数,所以数列中有40512032+=个0,所以C 正确; D 选项,n S 的值与n 的奇偶有关()()11531531n n n n S n −−⎧⋅−⎪=⎨⋅+⎪⎩为奇数为偶数,所以D 错误. 故选:ABC.【点睛】方法点睛:学生在理解相关新概念、新法则 (公式)之后,运用学过的知识,结合已掌握的技能,通过推理、运算等解决问题.在新环境下研究“旧”性质.主要是将新性质应用在“旧”性质上,创造性地证明更新的性质,落脚点仍然是数列求通项或求和. 三、填空题12.已知等差数列{}n a 中,24a =,616a =,若在数列{}n a 每相邻两项之间插入三个数,使得新数列也是一个等差数列,则新数列的第41项为___. 【答案】31【解析】设等差数列{}n a 的公差为d ,则62123624a a d −===−, 在数列{}n a 每相邻两项之间插入三个数,则新的等差数列{}n b 的公差为344d =, 故新数列的首项为431−=,故通项公式为()33111444n b n n =+−=+, 故4131413144b =⨯+=. 故答案为:3113.箱子中装有5个大小相同的小球,其中3个红球、2个白球.从中随机抽出2个球,在已知抽到红球的条件下,则2个球都是红球的概率为 .14.已知n S 是各项均为正实数的数列{}n a 的前n 项和,221111,60n n n n a a a a a ++=−−=,若*,2270n n n n S a ma ∀∈−+≥N ,则实数m 的取值范围是 .(2)记n n n b a c ⋅=,n T 为n c 的前n 项和,求n T .【解】(1)解:由已知可得32112127a b a b d q d q =++=++=+①, ()()22231122212a b a d b q d q −=+−=+−=②,联立①②,得()()26320q q q q +−=+−=,解得3q =−或2q,2q,代入①式可得在曲线()y f x =上(1)3f '⇒−=,21a a ++−(1n ⋅++=,)1+;()(1nn −−⋅,)()(1212233445212222k k k k k ⎡+++⋅⋅−⋅+⋅−⋅++−⋅−⋅+⎣[]12224222k +⋅−⋅−⋅−−⋅()()222224221k k k k k k k k =+−+++=+−+=,即T 2n =n 2.18.已知数列{}n a 的前 n 项和为n S ,()*∈−=N n S a n n 2.(1)求数列{}n a 的通项公式; (2)是否存在实数λ ,使数列⎭⎬⎫⎩⎨⎧++n n n S 2λλ为等差数列?若存在, 求出λ的值; 若不存在,请说明理由; (3)已知数列{}n b ,()()1121++=+−n n nn a a b ,其前 n 项和为n T ,求使得442m T m n<<−对所有*N n ∈都成立的自然数m 的值.的一动点,PAB 面积的最大值为C 交于,D 两点,记ODE 的面积为,DN EN 的斜率分别为12,k k .联立221431x y x my ⎧+=⎪⎨⎪=+⎩,消去x 可得()234m y +所以()()222Δ3636341441m m m =++=+且12122269,3434m y y y y m m +=−=−++, ODES=1,t t =≥2631t t =+试卷第11页,共11页。
江西省南昌市江西师范大学附属中学2024-2025学年高一上学期期中考试数学试卷一、单选题1.已知集合{}{}220,1||A x x B x x =+>=>,则A B = ()A .{}|21x x -<<B .{}|1x x >C .{|21x x -<<-或}1x >D .{|1x x <-或}1x >2.已知集合{}{}1,1,2,41,2,4,16M N =-=,.给出下列四个对应法则:①1y x=;②1y x =+;③y x =;④2y x =.请由函数定义判断,其中能构成从M 到N 的函数的是()A .①③B .①②C .③④D .②④3.已知函数()f x 在[)0,+∞上单调递减,则对实数120,0x x >>,“12x x >”是“()()12f x f x <”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4.函数()233xx f x =-的大致图象是()A .B .C .D .5.若函数()y f x =为奇函数,则它的图象必经过点()A .()0,0B .()(),a f a --C .()(),a f a -D .()(),a f a ---6.已知函数11(0,1)x y a a a -=+>≠的图像恒过定点A ,且点A 在直线(,0)y mx n m n =+>上,则11m n+的最小值为()A .4B .1C .2D .327.设()f x 是定义在R 上的奇函数、对任意()12,0,x x ∈+∞,且12x x ≠,都有()()2121f x f x x x ->-且(1)0f =、则不等式()0xf x >的解集为()A .(1,0)(1,)-+∞B .(,1)(0,1)-∞-C .(,0)(1,)-∞⋃+∞D .(,1)(1,)-∞-+∞ 8.已知函数()2,123,1x a a x f x ax ax a x ⎧+≥=⎨-+-+<⎩(0a >且1a ≠),若函数()f x 的值域为R ,则实数a 的取值范围是()A .20,3⎛⎤⎝⎦B .31,2⎛⎤ ⎥⎝⎦C .[)2,+∞D .[)3,+∞二、多选题9.下列说法正确的是()A .命题“0x ∀>,都有e 1x x >+的否定是“0x ∃>,使得e 1≤+x xB .若0a b >>,则11a ab b+>+C .()xf x x =与()1,01,0x g x x ≥⎧=⎨-<⎩表示同一函数D .函数()y f x =的定义域为[]2,3,则函数()21y f x =-的定义域为3,22⎡⎤⎢⎥⎣⎦10.已知函数()e 1e 1x x f x -=+,则下列结论正确的是()A .函数()f x 的定义域为RB .函数()f x 的值域为()1,1-C .()()0f x f x +-=D .函数()f x 为减函数11.已知函数()f x 的定义域为R ,其图象关于()1,2中心对称.若()()424f x f x x --=-,则()A .()()4214f x f x -+-=B .()()244f f +=C .()12y f x =+-为奇函数D .()22y f x x =++为偶函数三、填空题12()1132081π3274⎛⎫⎛⎫--+= ⎪ ⎪⎝⎭⎝⎭13.已知幂函数()()215m f x m m x -=+-在0,+∞上单调递减,则m =.14.将()22xx af x =-的图象向右平移2个单位后得曲线1C ,将函数=的图象向下平移2个单位后得曲线2C ,1C 与2C 关于x 轴对称.若()()()f x F x g x a=+的最小值为m 且2m >+则实数a 的取值范围为四、解答题15.已知集合U 为实数集,{5A x x =≤-或}8x ≥,{}121B x a x a =-≤≤+.(1)若5a =,求()U A B ⋂ð;(2)设命题p :x A ∈;命题q :x B ∈,若命题p 是命题q 的必要不充分条件,求实数a 的取值范围.16.已知函数()()3211f x x ax b x =++-+是定义在R 上的奇函数.(1)求a ,b 的值;(2)解不等式()3279333x x x xf >+-⨯+.17.已知定义域为R 的奇函数()21212x x f x =-+(1)判断函数()f x 的单调性,并用定义加以证明;(2)若对任意的[]1,2x ∈,不等式()()²²40f x mx f x -++>成立,求实数m 的取值范围.18.已知0a >且1a ≠,函数()4,02,0x a x x h x x -⎧≥=⎨<⎩,满足()()11h a h a -=-,设()x p x a -=.(1)若()()()231p x f x p x +=+,[)0,x ∞∈+,求函数()f x 的最小值;(2)函数()()()231p x f x p x +=+,()21g x x b x =-+-,若对[]11,1x ∀∈-,都存在[)20,x ∈+∞,使得()()21f x g x =,求b 的取值范围.19.对于定义在区间[],a b 上的函数f (x ),若()(){}[]()|,f P x max f t a t x x a b =≤≤∈.(1)已知()()[]121,2,0,1xf xg x x x ⎛⎫==∈ ⎪⎝⎭试写出()f P x 、()g P x 的表达式;(2)设0a >且1a ≠,函数()()2131,12x xf x a a a x ⎡⎤=+-⨯-∈⎢⎥⎣⎦,,如果()f P x 与()f x 恰好为同一函数,求a 的取值范围;(3)若()(){}[]()min ,f Q x f t a t x x a b =≤≤∈存在最小正整数k ,使得()()()f f P x Q x k x a -≤-对任意的[],x a b ∈成立,则称函数()f x 为[],a b 上的"k 阶收缩函数",已知1b >,函数()4f x x x=+是[]1,b 上的“3阶收缩函数”,求b 的取值范围.。
西华师范大学附属中学高一年级第一次月考英语试卷英语试题总分:150分考试时间:100分钟命题人、审题人:高一英语组第一部分听力(共两节,满分30分)第一节(共5小题;每小题1.5分,满分7.5分)听下面5段对话。
每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项。
听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。
每段对话仅读一遍。
1. Where does the conversation take place?A. At home.B. In a supermarket.C. At a restaurant.2: What does the man want to do?A. Find a job.B. Start a company.C. Take an interview.3. What may be the reason for Mary’s sleep problem according to the man?A. Exam stress.B. Energy drinks.C. Boiled water.4. What’s the relationship between the speakers?A. Husband and wife.B. Boss and secretary.C. Customer and waitress.5. What are the speakers mainly talking about?A. A pity.B.A team.C. A match.第二节(共15小题;每小题1.5分,满分22.5分)听下面5段对话或独白。
每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项。
听每段对话或独白前,你将有时间阅读各个小题,每小题5秒钟;听完后,各小题将给出5秒钟作答时间。
每段对话或独白读两遍。
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江西省南昌市江西师范大学附属中学2024-2025学年高二上学期期中考试数学试题一、单选题1.已知直线3(2)20x a y ---=与直线80x ay ++=互相垂直,则a =()A .1B .3-C .1-或3D .3-或12.已知椭圆22:1x C y m+=,则“2m =”是“椭圆C ”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3.如图,空间四边形OABC 中,,,OA a OB b OC c === ,点M 在OA 上,且满足2OM MA =,点N 为BC 的中点,则MN =()A .121232a b c-+ B .211322a b c -++C .111222a b c+- D .221332a b c+- 4.点1F ,2F 为椭圆C 的两个焦点,若椭圆C 上存在点P ,使得1290F PF ∠=,则椭圆C 方程可以是()A .221259x y +=B .2212516x y +=C .22169x y +=D .221169x y +=5.若21x -=22x y +的最小值为()A .1B .2C .4D .146.若实数,x y 满足22(2)1x y -+=,则下列结论错误的是()A .24x y +≤B .()122x y -≤C .y x ≤D .25x y -≤7.已知12,F F 分别是双曲线22:1412x yE -=的左、右焦点,M 是E 的左支上一点,过2F 作12F MF ∠角平分线的垂线,垂足为,N O 为坐标原点,则||ON =()A .4B .2C .3D .18.从椭圆2222:1(0)x y C a b a b+=>>外一点0,0向椭圆引两条切线,切点分别为,A B ,则直线AB 称作点P 关于椭圆C 的极线,其方程为00221x x y ya b +=.现有如图所示的两个椭圆12,C C ,离心率分别为12,e e ,2C 内含于1C ,椭圆1C 上的任意一点M 关于2C 的极线为l ,若原点O 到直线l 的距离为1,则2212e e -的最大值为()A .12B .13C .15D .14二、多选题9.关于曲线22:1E mx ny +=,下列说法正确的是()A .若曲线E 表示两条直线,则0,0m n =>或0,0n m =>B .若曲线E 表示圆,则0m n =>C .若曲线E 表示焦点在x 轴上的椭圆,则0m n >>D .若曲线E 表示双曲线,则0mn <10.已知圆22:4O x y +=,则()A .圆O 与直线10mx y m +--=必有两个交点B .圆O 上存在4个点到直线:0l x y -+=的距离都等于1C .若圆O 与圆22680x y x y m +--+=恰有三条公切线,则16m =D .已知动点P 在直线40x y +-=上,过点P 向圆O 引两条切线,A ,B 为切点,则||||OP AB 的最小值为811.如图,曲线C 是一条“双纽线”,其C 上的点满足:到点()12,0F -与到点()22,0F 的距离之积为4,则下列结论正确的是()A .点()D 在曲线C 上B .点(),1(0)M x x >在C 上,则1MF =C .点Q 在椭圆22162x y+=上,若12FQ F Q ⊥,则Q C ∈D .过2F 作x 轴的垂线交C 于,A B 两点,则2AB <三、填空题12.设12,F F 是双曲线C :2213y x -=的两个焦点,O 为坐标原点,点P 在C 上且120PF PF ⋅= ,则12PF F 面积为.13.已知,A B 为椭圆()222210x y a b a b+=>>上的左右顶点,设点P 为椭圆上异于,A B 的任意一点,直线,PA PB 的斜率分别为12,k k ,若椭圆离心率为2,则12k k ⋅为.14.如图,在棱长为3的正方体1111ABCD A B C D -中,P 在正方形11CC D D 及其内部上运动,若tan 2tan PAD PBC ∠∠=,则点P 的轨迹的长度为.四、解答题15.已知圆22:4O x y +=.(1)若线段AB 端点B 的坐标是(4,2),端点A 在圆O 上运动,求线段AB 的中点D 的轨迹方程;(2)若,EF GH 为圆22:4O x y +=的两条相互垂直的弦,垂足为M ,求四边形EGFH 的面积S 的最大值.16.在四棱锥P ABCD -中,底面ABCD 是边长为2的正方形,PC PD ⊥,二面角A CD P --为直二面角.(1)求证:PB PD ⊥;(2)当PC PD =时,求直线PC 与平面PAB 所成角的正弦值.17.给定椭圆C :()222210+=>>x y a b a b,称圆心在原点O C 的“准圆”.已知椭圆C 的一个焦点为)F ,其短轴的一个端点到点F(1)求椭圆C 和其“准圆”的方程;(2)若点A ,B 是椭圆C 的“准圆”与x 轴的两交点,P 是椭圆C 上的一个动点,求AP BP ⋅的取值范围.18.已知O 为坐标原点,圆O :221x y +=,直线l :y x m =+(01m ≤<),如图,直线l 与圆O 相交于A (A 在x 轴的上方),B 两点,圆O 与x 轴交于,M N 两点(M 在N 的左侧),将平面xOy 沿x 轴折叠,使y 轴正半轴和x 轴所确定的半平面(平面AMN )与y 轴负半轴和x 轴所确定的半平面(平面BMN )互相垂直,再以O 为坐标原点,折叠后原y 轴负半轴,原x 轴正半轴,原y 轴正半轴所在直线分别为x ,y ,z 轴建立如图所示的空间直角坐标系.(1)若0m =.(ⅰ)求三棱锥A BMN -的体积;(ⅱ)求二面角A BN M --的余弦值.(2)是否存在m ,使得AB 折叠后的长度与折叠前的长度之比为6?若存在,求m 的值;若不存在,请说明理由.19.“工艺折纸”是一种把纸张折成各种不同形状物品的艺术活动,在我国源远流长,某些折纸活动蕴含丰富的数学知识,例如:用一张圆形纸片,按如下步骤折纸(如图):步骤1:设圆心是E ,在圆内异于圆心处取一定点,记为F ;步骤2:把纸片折叠,使圆周正好通过点F (即折叠后图中的点A 与点F 重合);步骤3:把纸片展开,并留下一道折痕,记折痕与AE 的交点为P ;步骤4:不停重复步骤2和3,就能得到越来越多的折痕.现取半径为4的圆形纸片,设点F 到圆心E 的距离为按上述方法折纸.以线段EF 的中点为原点,线段EF 所在直线为x 轴建立平面直角坐标系xOy ,记动点P 的轨迹为曲线C .(1)求C 的方程;(2)设轨迹C 与x 轴从左到右的交点为点A ,B ,点P 为轨迹C 上异于A ,B ,的动点,设PB 交直线4x =于点T ,连结AT 交轨迹C 于点Q .直线AP 、AQ 的斜率分别为AP k 、AQ k .(i )求证:AP AQ k k ⋅为定值;(ii)证明直线PQ经过x轴上的定点,并求出该定点的坐标.。
大联考湖南师大附中2025届高三月考试卷(一)数学命题人:高三数学备课组 审题人:高三数学备课组时量:120分钟 满分:150分一、选择题:本题共8小题,每小题5分,共40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{}()260,{lg 10}A x x x B x x =+-≤=-<∣∣,则A B = ( )A. {}32xx -≤≤∣ B. {32}x x -≤<∣C. {12}xx <≤∣ D. {12}xx <<∣【答案】D【解析】【分析】通过解一元二次不等式和对数函数的定义域,求出集合,A B ,再求交集.【详解】集合{}()32,{lg 10}{12}A x x B x x x x =-≤≤=-<=<<∣∣∣,则{12}A B xx ⋂=<<∣,故选:D .2. 若复数z 满足()1i 3i z +=-+(i 是虚数单位),则z 等于( )A. B. 54 C. D. 【答案】C【解析】【分析】由复数的除法运算计算可得12i z =-+,再由模长公式即可得出结果.【详解】依题意()1i 3i z +=-+可得()()()()3i 1i 3i 24i 12i 1i 1i 1i 2z -+--+-+====-+++-,所以z ==.故选:C 3. 已知平面向量()()5,0,2,1a b ==- ,则向量a b + 在向量b 上的投影向量为( )A. ()6,3-B. ()4,2-C. ()2,1- D. ()5,0【答案】A【解析】【分析】根据投影向量的计算公式即可求解.【详解】()()7,1,15,a b a b b b +=-+⋅=== 所以向量a b + 在向量b 上的投影向量为()()236,3||a b b b b b +⋅==- .故选:A4. 记n S 为等差数列{}n a 的前n 项和,若396714,63a a a a +==,则7S =( )A. 21B. 19C. 12D. 42【答案】A【解析】【分析】根据等差数列的性质,即可求解公差和首项,进而由求和公式求解.【详解】{}n a 是等差数列,396214a a a ∴+==,即67a =,所以67769,a a a a ==故公差76162,53d a a a a d =-=∴=-=-,()767732212S ⨯∴=⨯-+⨯=,故选:A 5. 某校高二年级下学期期末考试数学试卷满分为150分,90分以上(含90分)为及格.阅卷结果显示,全年级1200名学生的数学成绩近似服从正态分布,试卷的难度系数(难度系数=平均分/满分)为0.49,标准差为22,则该次数学考试及格的人数约为( )附:若()2,X N μσ~,记()()p k P k X k μσμσ=-≤≤+,则()()0.750.547,10.683p p ≈≈.A. 136人B. 272人C. 328人D. 820人【答案】B【解析】【分析】首先求出平均数,即可得到学生的数学成绩2~(73.5,22)X N ,再根据所给条件求出(5790)P X ≤≤,即可求出(90)P X ≥,即可估计人数.【详解】由题得0.4915073.5,22μσ=⨯==,()()(),0.750.547p k P k X k p μσμσ=-≤≤+≈ ,()5790P X ∴≤≤()0.750.547p =≈,()()900.510.5470.2265P X ≥=⨯-=,∴该校及格人数为0.22651200272⨯≈(人),故选:B .6. 已知()π5,0,,cos ,tan tan 426αβαβαβ⎛⎫∈-=⋅= ⎪⎝⎭,则αβ+=( )A. π6 B. π4 C. π3 D. 2π3【答案】D【解析】【分析】利用两角差的余弦定理和同角三角函数的基本关系建立等式求解,再由两角和的余弦公式求解即可.【详解】由已知可得5cos cos sin sin 6sin sin 4cos cos αβαβαβαβ⎧⋅+⋅=⎪⎪⎨⋅⎪=⋅⎪⎩,解得1cos cos 62sin sin 3αβαβ⎧⋅=⎪⎪⎨⎪⋅=⎪⎩,,()1cos cos cos sin sin 2αβαβαβ∴+=⋅-⋅=-,π,0,2αβ⎛⎫∈ ⎪⎝⎭,()0,παβ∴+∈,2π,3αβ∴+=,故选:D .7. 已知12,F F 是双曲线22221(0)x y a b a b-=>>的左、右焦点,以2F 为圆心,a 为半径的圆与双曲线的一条渐近线交于,A B 两点,若123AB F F >,则双曲线的离心率的取值范围是( )A. ⎛ ⎝B. ⎛ ⎝C. (D. (【答案】B【解析】【分析】根据双曲线以及圆的方程可求得弦长AB =,再根据不等式123AB F F >整理可得2259c a <,即可求得双曲线的离心率的取值范围.【详解】设以()2,0F c 为圆心,a 为半径的圆与双曲线的一条渐近线0bx ay -=交于,A B 两点,则2F 到渐近线0bx ay -=的距离d b ==,所以AB =,因为123AB F F >,所以32c ⨯>,可得2222299a b c a b ->=+,即22224555a b c a >=-,可得2259c a <,所以2295c a <,所以e <,又1e >,所以双曲线的离心率的取值范围是⎛ ⎝.故选:B 8. 已知函数()220log 0x a x f x x x ⎧⋅≤=⎨>⎩,,,,若关于x 的方程()()0f f x =有且仅有两个实数根,则实数a 的取值范围是( )A. ()0,1 B. ()(),00,1-∞⋃ C. [)1,+∞ D. ()()0,11,+∞ 【答案】C【解析】【分析】利用换元法设()u f x =,则方程等价为()0f u =,根据指数函数和对数函数图象和性质求出1u =,利用数形结合进行求解即可.【详解】令()u f x =,则()0f u =.①当0a =时,若()0,0u f u ≤=;若0u >,由()2log 0f u u ==,得1u =.所以由()()0f f x =可得()0f x ≤或()1f x =.如图所示,满足()0f x ≤的x 有无数个,方程()1f x =只有一个解,不满足题意;②当0a ≠时,若0≤u ,则()20uf u a =⋅≠;若0u >,由()2log 0f u u ==,得1u =.所以由()()0f f x =可得()1f x =,当0x >时,由()2log 1f x x ==,可得2x =,因为关于x 的方程()()0ff x =有且仅有两个实数根,则方程()1f x =在(,0∞-]上有且仅有一个实数根,若0a >且()(]0,20,x x f x a a ≤=⋅∈,故1a ≥;若0a <且()0,20xx f x a ≤=⋅<,不满足题意.综上所述,实数a 的取值范围是[)1,+∞,故选:C .二、多选题:本题共36分,共18分.在每小题给出的选项中,有多项符合题目要求.全部选对的得6分,部分选对的得部分分,有选错的得0分9. 如图,在正方体111ABCD A B C D -中,E F M N ,,,分别为棱111AA A D AB DC ,,,的中点,点P 是面1B C 的中心,则下列结论正确的是( )A. E F M P ,,,四点共面B. 平面PEF 被正方体截得的截面是等腰梯形C. //EF 平面PMND. 平面MEF ⊥平面PMN【答案】BD 【解析】【分析】可得过,,E F M 三点的平面为一个正六边形,判断A ;分别连接,E F 和1,B C ,截面1C BEF 是等腰梯形,判断B ;分别取11,BB CC 的中点,G Q ,易证EF 显然不平行平面QGMN ,可判断C ;EM ⊥平面PMN ,可判断D.【详解】对于A :如图经过,,E F M 三点的平面为一个正六边形EFMHQK ,点P 在平面外,,,,E F M P ∴四点不共面,∴选项A 错误;对于B :分别连接,E F 和1,B C ,则平面PEF 即平面1C BEF ,截面1C BEF 是等腰梯形,∴选项B 正确;对于C :分别取11,BB CC 的中点,G Q ,则平面PMN 即为平面QGMN ,由正六边形EFMHQK ,可知HQ EF ,所以MQ 不平行于EF ,又,EF MQ ⊂平面EFMHQK ,所以EF MQ W = ,所以EF I 平面QGMN W =,所以EF 不平行于平面PMN ,故选项C 错误;对于D :因为,AEM BMG 是等腰三角形,45AME BMG ∴∠=∠=︒,90EMG ∴∠=︒,EM MG ∴⊥,,M N 是,AB CD 的中点,易证MN AD ∥,由正方体可得AD ⊥平面11ABB A ,MN ∴⊥平面11ABB A ,又ME ⊂平面11ABB A ,EM MN ∴⊥,,MG MN ⊂ 平面PMN ,EM ∴⊥平面GMN ,EM ⊂ 平面MEF ,∴平面MEF ⊥平面,PMN 故选项D 正确.故选:BD .10. 已知函数()5π24f x x ⎛⎫=+ ⎪⎝⎭,则( )A. ()f x 的一个对称中心为3π,08⎛⎫ ⎪⎝⎭B. ()f x 的图象向右平移3π8个单位长度后得到的是奇函数的图象C. ()f x 在区间5π7π,88⎡⎤⎢⎥⎣⎦上单调递增D. 若()y f x =在区间()0,m 上与1y =有且只有6个交点,则5π13π,24m ⎛⎤∈ ⎥⎝⎦【答案】BD【解析】【分析】代入即可验证A ,根据平移可得函数图象,即可由正弦型函数的奇偶性求解B ,利用整体法即可判断C ,由5πcos 24x ⎛⎫+= ⎪⎝⎭求解所以根,即可求解D.【详解】对于A ,由35π3π2π0848f ⎛⎫⎛⎫=+⨯=≠ ⎪ ⎪⎝⎭⎝⎭,故A 错误;对于B ,()f x 的图象向右平移3π8个单位长度后得:3π3π5ππ228842y f x x x x ⎡⎤⎛⎫⎛⎫⎛⎫=-=-+=+= ⎪ ⎪ ⎪⎢⎥⎝⎭⎝⎭⎝⎭⎣⎦,为奇函数,故B 正确;对于C ,当5π7π,88x ⎡⎤∈⎢⎥⎣⎦时,则5π5π2,3π42x ⎡⎤+∈⎢⎥⎣⎦,由余弦函数单调性知,()f x 在区间5π7π,88⎡⎤⎢⎥⎣⎦上单调递减,故C 错误;对于D ,由()1f x =,得5πcos 24x ⎛⎫+= ⎪⎝⎭ππ4x k =+或ππ,2k k +∈Z ,()y f x =在区间()0,m 上与1y =有且只有6个交点,其横坐标从小到大依次为:ππ5π3π9π5π,,,,,424242,而第7个交点的横坐标为13π4,5π13π24m ∴<≤,故D 正确.故选:BD11. 已知定义在R 上的偶函数()f x 和奇函数()g x 满足()()21f x g x ++-=,则( )A. ()f x 的图象关于点()2,1对称B. ()f x 是以8为周期的周期函数C. ()20240g =D. 20241(42)2025k f k =-=∑【答案】ABC【解析】【分析】根据函数奇偶性以及所满足的表达式构造方程组可得()()222f x f x ++-=,即可判断A 正确;利用对称中心表达式进行化简计算可得B 正确,可判断()g x 也是以8为周期的周期函数,即C 正确;根据周期性以及()()42f x f x ++=计算可得20241(42)2024k f k =-=∑,可得D 错误.【详解】由题意()()()(),f x f x g x g x -=-=-,且()()()00,21g f x g x =++-=,即()()21f x g x +-=①,用x -替换()()21f x g x ++-=中的x ,得()()21f x g x -+=②,由①+②得()()222f x f x ++-=所以()f x 的图象关于点(2,1)对称,且()21f =,故A 正确;由()()222f x f x ++-=,可得()()()()()42,422f x f x f x f x f x ++-=+=--=-,所以()()()()82422f x f x f x f x ⎡⎤+=-+=--=⎣⎦,所以()f x 是以8为周期的周期函数,故B 正确;由①知()()21g x f x =+-,则()()()()882121g x f x f x g x +=++-=+-=,故()()8g x g x +=,因此()g x 也是以8为周期的周期函数,所以()()202400g g ==,C 正确;又因为()()42f x f x ++-=,所以()()42f x f x ++=,令2x =,则有()()262f f +=,令10x =,则有()()10142,f f +=…,令8090x =,则有()()809080942f f +=,所以1012(2)(6)(10)(14)(8090)(8094)2222024f f f f f f ++++++=+++= 个所以20241(42)(2)(6)(10)(14)(8090)(8094)2024k f k f f f f f f =-=++++++=∑ ,故D 错误.故选:ABC【点睛】方法点睛:求解函数奇偶性、对称性、周期性等函数性质综合问题时,经常利用其中两个性质推得第三个性质特征,再进行相关计算.三、填空题:本题共3小题,每小题5分,共15分.12. 6(31)x y +-的展开式中2x y 的系数为______.【答案】180-【解析】【分析】根据题意,由条件可得展开式中2x y 的系数为213643C C (1)⋅-,化简即可得到结果.【详解】在6(31)x y +-的展开式中,由()2213264C C 3(1)180x y x y ⋅⋅-=-,得2x y 的系数为180-.故答案为:180-.13. 已知函数()f x 是定义域为R 的奇函数,当0x >时,()()2f x f x '->,且()10f =,则不等式()0f x >的解集为__________.【答案】()()1,01,-⋃+∞【解析】【分析】根据函数奇偶性并求导可得()()f x f x ''-=,因此可得()()2f x f x '>,可构造函数()()2x f x h x =e并求得其单调性即可得()f x 在()1,+∞上大于零,在()0,1上小于零,即可得出结论.【详解】因为()f x 为奇函数,定义域为R ,所以()()f x f x -=-,两边同时求导可得()()f x f x ''--=-,即()()f x f x ''-=且()00f =,又因为当0x >时,()()2f x f x '->,所以()()2f x f x '>.构造函数()()2x f x h x =e ,则()()()22x f x f x h x '-'=e,所以当0x >时,()()0,h x h x '>在()0,∞+上单调递增,又因为()10f =,所以()()10,h h x =在()1,+∞上大于零,在()0,1上小于零,又因为2e 0x >,所以()f x 在()1,+∞上大于零,在()0,1上小于零,因为()f x 为奇函数,所以()f x 在(),1∞--上小于零,在()1,0-上大于零,综上所述,()0f x >的解集为()()1,01,-⋃+∞.故答案为:()()1,01,-⋃+∞14. 已知点C 为扇形AOB 的弧AB 上任意一点,且60AOB ∠=,若(),R OC OA OB λμλμ=+∈ ,则λμ+的取值范围是__________.【答案】⎡⎢⎣【解析】【分析】建系设点的坐标,再结合向量关系表示λμ+,最后应用三角恒等变换及三角函数值域求范围即可.【详解】方法一:设圆O 的半径为1,由已知可设OB 为x 轴的正半轴,O 为坐标原点,过O 点作x 轴垂线为y 轴建立直角坐标系,其中()()1,1,0,cos ,sin 2A B C θθ⎛ ⎝,其中π,0,3BOC θθ⎡⎤∠=∈⎢⎥⎣⎦,由(),R OC OA OB λμλμ=+∈ ,即()()1cos ,sin 1,02θθλμ⎛=+ ⎝,整理得1cos sin 2λμθθ+==,解得cos λμθ==,则ππcos cos ,0,33λμθθθθθ⎛⎫⎡⎤+==+=+∈ ⎪⎢⎥⎝⎭⎣⎦,ππ2ππ,,sin 3333θθ⎤⎡⎤⎛⎫+∈+∈⎥⎪⎢⎥⎣⎦⎝⎭⎦所以λμ⎡+∈⎢⎣.方法二:设k λμ+=,如图,当C 位于点A 或点B 时,,,A B C 三点共线,所以1k λμ=+=;当点C 运动到AB的中点时,k λμ=+==,所以λμ⎡+∈⎢⎣故答案为:⎡⎢⎣四、解答题:本题共5小题,共77分.解答应写出文字说明、证明过程或演算步骤.15. ABC V 的内角,,A B C 的对边分别为,,a b c ,已知22cos a b c B +=.(1)求角C ;(2)若角C 的平分线CD 交AB于点,D AD DB ==CD 的长.【答案】(1)2π3C = (2)3CD =【解析】【分析】(1)利用正弦定理及两角和的正弦定理整理得到()2cos 1sin 0C B +=,再利用三角形的内角及正弦函数的性质即可求解;(2)利用正弦定理得出3b a =,再由余弦定理求出4a =,12b =,再根据三角形的面积建立等式求解.【小问1详解】由22cos a b c B +=,根据正弦定理可得2sin sin 2sin cos A B C B +=,则()2sin sin 2sin cos B C B C B ++=,所以2sin cos 2cos sin sin 2sin cos B C B C B C B ++=,整理得()2cos 1sin 0C B +=,因为,B C 均为三角形内角,所以(),0,π,sin 0B C B ∈≠,因此1cos 2C =-,所以2π3C =.【小问2详解】因为CD 是角C的平分线,AD DB ==所以在ACD 和BCD △中,由正弦定理可得,,ππsin sin sin sin 33AD CD BD CDA B ==,因此sin 3sin B ADA BD==,即sin 3sin B A =,所以3b a =,又由余弦定理可得2222cos c a b ab C =+-,即222293a a a =++,解得4a =,所以12b =.又ABC ACD BCD S S S =+△△△,即111sin sin sin 222ab ACB b CD ACD a CD BCD ∠∠∠=⋅⋅+⋅⋅,即4816CD =,所以3CD =.16. 已知1ex =为函数()ln af x x x =的极值点.(1)求a 的值;(2)设函数()ex kxg x =,若对()120,,x x ∀∈+∞∃∈R ,使得()()120f x g x -≥,求k 的取值范围.【答案】(1)1a = (2)(]()10,-∞-+∞ ,【解析】【分析】(1)直接根据极值点求出a 的值;(2)先由(1)求出()f x 的最小值,由题意可得是求()g x 的最小值,小于等于()f x 的最小值,对()g x 求导,判断由最小值时的k 的范围,再求出最小值与()f x 最小值的关系式,进而求出k 的范围.【小问1详解】()()111ln ln 1a a f x ax x x x a x xα--=='+⋅+,由1111ln 10e e e a f a -⎛⎫⎛⎫⎛⎫=+= ⎪ ⎪⎪⎝⎭⎝⎭'⎭⎝,得1a =,当1a =时,()ln 1f x x ='+,函数()f x 在10,e ⎛⎫ ⎪⎝⎭上单调递减,在1,e∞⎛⎫+ ⎪⎝⎭上单调递增,所以1ex =为函数()ln af x x x =的极小值点,所以1a =.【小问2详解】由(1)知min 11()e e f x f ⎛⎫==- ⎪⎝⎭.函数()g x 的导函数()()1exg x k x -=-'①若0k >,对()1210,,x x k ∞∀∈+∃=-,使得()()12111e 1e k g x g f x k ⎛⎫=-=-<-<-≤ ⎪⎝⎭,即()()120f x g x -≥,符合题意.②若()0,0k g x ==,取11ex =,对2x ∀∈R ,有()()120f x g x -<,不符合题意.③若0k <,当1x <时,()()0,g x g x '<在(),1∞-上单调递减;当1x >时,()()0,g x g x '>在(1,+∞)上单调递增,所以()min ()1ek g x g ==,若对()120,,x x ∞∀∈+∃∈R ,使得()()120f x g x -≥,只需min min ()()g x f x ≤,即1e ek ≤-,解得1k ≤-.综上所述,k 的取值范围为(](),10,∞∞--⋃+.17. 已知四棱锥P ABCD -中,平面PAB ⊥底面,ABCD AD ∥,,,2,BC AB BC PA PB AB AB BC AD E ⊥====为AB 的中点,F 为棱PC 上异于,P C 的点.(1)证明:BD EF ⊥;(2)试确定点F 的位置,使EF 与平面PCD【答案】(1)证明见解析(2)F 位于棱PC 靠近P 的三等分点【解析】【分析】(1)连接,,PE EC EC 交BD 于点G ,利用面面垂直的性质定理和三角形全等,即可得证;(2)取DC 的中点H ,以E 为坐标原点,分别以,,EB EH EP 所在直线为,,x y z 轴建立,利用线面角公式代入即可求解.小问1详解】如图,连接,,PE EC EC 交BD 于点G .因为E 为AB 的中点,PA PB =,所以PE AB ⊥.因为平面PAB ⊥平面ABCD ,平面PAB ⋂平面,ABCD AB PE =⊂平面PAB ,所以PE ⊥平面ABCD ,因为BD ⊂平面ABCD ,所以BD ⊥.因为ABD BCE ≅ ,所以CEB BDA ∠∠=,所以90CEB ABD ∠∠+= ,所以BD EC ⊥,因为,,PE EC E PE EC ⋂=⊂平面PEC ,所以BD ⊥平面PEC .因为EF ⊂平面PEC ,所以BD EF ⊥.【小问2详解】如图,取DC 的中点H ,以E 为坐标原点,分别以,,EB EH EP 所在直线为,,x y z 轴建立空间直角坐标系,【设2AB =,则2,1,BC AD PA PB ====则()()()()0,0,1,1,2,0,1,1,0,0,0,0P C D E -,设(),,,(01)F x y z PF PC λλ=<<,所以()(),,11,2,1x y z λ-=-,所以,2,1x y z λλλ===-,即(),2,1F λλλ-.则()()()2,1,0,1,2,1,,2,1DC PC EF λλλ==-=-,设平面PCD 的法向量为(),,m a b c =,则00DC m PC m ⎧⋅=⎪⎨⋅=⎪⎩,,即2020a b a b c +=⎧⎨+-=⎩,,取()1,2,3m =--,设EF 与平面PCD 所成的角为θ,由cos θ=sin θ=.所以sin cos ,m EF m EF m EF θ⋅====整理得2620λλ-=,因为01λ<<,所以13λ=,即13PF PC = ,故当F 位于棱PC 靠近P 的三等分点时,EF 与平面PCD18. 在平面直角坐标系xOy 中,抛物线21:2(0)C y px p =>的焦点到准线的距离等于椭圆222:161C x y +=的短轴长,点P 在抛物线1C 上,圆222:(2)E x y r -+=(其中01r <<).(1)若1,2r Q =为圆E 上的动点,求线段PQ长度的最小值;(2)设()1,D t 是抛物线1C 上位于第一象限的一点,过D 作圆E 的两条切线,分别交抛物线1C 于点,M N .证明:直线MN 经过定点.【答案】(1(2)证明见解析【解析】【分析】(1)根据椭圆的短轴可得抛物线方程2y x =,进而根据两点斜率公式,结合三角形的三边关系,即可由二次函数的性质求解,(2)根据两点坐标可得直线,MN DM 的直线方程,由直线与圆相切可得,a b 是方程()()()2222124240rx r x r -+-+-=的两个解,即可利用韦达定理代入化简求解定点.【小问1详解】由题意得椭圆的方程:221116y x +=,所以短半轴14b =所以112242p b ==⨯=,所以抛物线1C 的方程是2y x =.设点()2,P t t ,则111222PQ PE ≥-=-=≥,所以当232ι=时,线段PQ.【小问2详解】()1,D t 是抛物线1C 上位于第一象限的点,21t ∴=,且()0,1,1t D >∴设()()22,,,M a a N b b ,则:直线()222:b a MN y a x a b a --=--,即()21y a x a a b -=-+,即()0x a b y ab -++=.直线()21:111a DM y x a --=--,即()10x a y a -++=.由直线DMr =,即()()()2222124240r a r a r -+-+-=..同理,由直线DN 与圆相切得()()()2222124240r b r b r -+-+-=.所以,a b 是方程()()()2222124240r x r x r -+-+-=的两个解,22224224,11r r a b ab r r --∴+==--代入方程()0x a b y ab -++=得()()222440x y r x y +++---=,220,440,x y x y ++=⎧∴⎨++=⎩解得0,1.x y =⎧⎨=-⎩∴直线MN 恒过定点()0,1-.【点睛】圆锥曲线中定点问题的两种解法(1)引进参数法:先引进动点的坐标或动线中系数为参数表示变化量,再研究变化的量与参数何时没有关系,找到定点.(2)特殊到一般法:先根据动点或动线的特殊情况探索出定点,再证明该定点与变量无关.技巧:若直线方程为()00y y k x x -=-,则直线过定点()00,x y ;若直线方程为y kx b =+ (b 为定值),则直线过定点()0,.b 19. 龙泉游泳馆为给顾客更好的体验,推出了A 和B 两个套餐服务,顾客可选择A 和B 两个套餐之一,并在App 平台上推出了优惠券活动,下表是该游泳馆在App 平台10天销售优惠券情况.日期t 12345678910销售量千张1.91.982.22.362.432592.682.762.70.4经计算可得:10101021111 2.2,118.73,38510i i i i i i i y y t y t =======∑∑∑.(1)因为优惠券购买火爆,App 平台在第10天时系统出现异常,导致当天顾客购买优惠券数量大幅减少,已知销售量y 和日期t 呈线性关系,现剔除第10天数据,求y 关于t 的经验回归方程结果中的数值用分数表示;..(2)若购买优惠券的顾客选择A 套餐的概率为14,选择B 套餐的概率为34,并且A 套餐可以用一张优惠券,B 套餐可以用两张优惠券,记App 平台累计销售优惠券为n 张的概率为n P ,求n P ;(3)记(2)中所得概率n P 的值构成数列{}()N n P n *∈.①求n P 的最值;②数列收敛的定义:已知数列{}n a ,若对于任意给定的正数ε,总存在正整数0N ,使得当0n N >时,n a a ε-<,(a 是一个确定的实数),则称数列{}n a 收敛于a .根据数列收敛的定义证明数列{}n P 收敛.参考公式:()()()1122211ˆˆ,n niii ii i nniii i x x y y x y nx yay bx x x xnx====---==---∑∑∑∑.【答案】(1)673220710001200y t =+ (2)433774nn P ⎛⎫=+⋅- ⎪⎝⎭(3)①最大值为 1316,最小值为14;②证明见解析【解析】【分析】(1)计算出新数据的相关数值,代入公式求出 ,ab 的值,进而得到y 关于t 的回归方程;(2)由题意可知1213,(3)44n n n P P P n --=+≥,其中12113,416P P ==,构造等比数列,再利用等比数列的通项公式求解;(3)①分n 为偶数和n 为奇数两种情况讨论,结合指数函数的单调性求解;②利用数列收敛的定义,准确推理、运算,即可得证.【小问1详解】解:剔除第10天的数据,可得 2.2100.42.49y ⨯-==新,12345678959t ++++++++==新,则9922111119.73100.4114,73,38510285i i i i t y t ==⎛⎫⎛⎫=-⨯==-= ⎪ ⎪⎝⎭⎝⎭∑∑新新,所以912922119114,7395 2.4673ˆ2859560009i i i i t y t y b t t ==⎛⎫- ⎪-⨯⨯⎝⎭===-⨯⎛⎫- ⎪⎝⎭∑∑新新新新新,可得6732207ˆ 2.4560001200a=-⨯=,所以6732207ˆ60001200yt =+.【小问2详解】解:由题意知1213,(3)44n n n P P P n --=+≥,其中12111313,444416P P ==⨯+=,所以11233,(3)44n n n n P P P P n ---+=+≥,又由2131331141644P P +=+⨯=,所以134n n P P -⎧⎫+⎨⎬⎩⎭是首项为1的常数列,所以131,(2)4n n P P n -+=≥所以1434(2)747n n P P n --=--≥,又因为1414974728P -=-=-,所以数列47n P ⎧⎫-⎨⎬⎩⎭是首项为928-,公比为34-的等比数列,故143)74n n P --=-,所以1934433(()2847774n n n P -=--+=+-.【小问3详解】解:①当n 为偶数时,19344334()(28477747n n n P -=--+=+⋅>单调递减,最大值为21316P =;当n 为奇数时,19344334()(28477747n n n P -=--+=-⋅<单调递增,最小值为114P =,综上可得,数列{}n P 的最大值为1316,最小值为14.②证明:对任意0ε>总存在正整数0347[log ()]13N ε=+,其中 []x 表示取整函数,当 347[log ()]13n ε>+时,347log ()34333333()()()7747474n n n P εε-=⋅-=⋅<⋅=,所以数列{}n P 收敛.【点睛】知识方法点拨:与新定义有关的问题的求解策略:1、通过给出一个新的定义,或约定一种新的运算,或给出几个新模型来创设新问题的情景,要求在阅读理解的基础上,依据题目提供的信息,联系所学的知识和方法,实心信息的迁移,达到灵活解题的目的;2、遇到新定义问题,应耐心读题,分析新定义的特点,弄清新定义的性质,按新定义的要求,“照章办事”,逐条分析、运算、验证,使得问题得以解决.方法点拨:与数列有关的问题的求解策略:3、若新定义与数列有关,可得利用数列的递推关系式,结合数列的相关知识进行求解,多通过构造的分法转化为等差、等比数列问题求解,求解过程灵活运用数列的性质,准确应用相关的数列知识.。
2023-2024学年江西省九校联考高三下学期3月月考英语试题Discover the Huge Health Benefits of Strength TrainingOne of the best ways to stay fit and healthy as you age is to do strength and power training exercises. It is known that when you are in your thirties, you will begin to lose muscle mass. This loss actually contributes to achy joints, the increased risk of injury, and the “middle-age spread” we all fear. What’s more, the older you get, the faster muscle mass loses. It means that eventually, simple tasks like getting out of a chair and climbing stairs can become more difficult.Strength training can help you build muscles, make you strong, increase your staying power and make everyday activities eas ier. By combining strength and power training exercises, you’ll not only get stronger, but also improve your reaction speed. As you grow older, that’s critical because it can help prevent falls. Here is a book, Strength and Power Training for All Ages, for your reference.Common sense about fitness in the book:·The key muscles to work for an injury-free body·How to tell how much weight is suitable for you·How to strengthen the bones most likely to break·How to take pressure off your knees when walking or running·Why you’ll want to apply heat to sore joints before you exerciseFour total body workouts in the book:·Build bones·Fight diseases·Improve balance·Strengthen muscles &Increase muscle powerGet a copy, start training, and then you’ll discover a whole new self.1. What will happen as people age according to paragraph 1?A.They will need less exercise.B.They will improve reaction speed.C.They will experience muscle loss.D.They will have better staying power.2. What does Strength and Power Training for All Ages mainly teach people to do?A.Train their brains. B.Build a sound body.C.Treat bone diseases. D.Cut down their weight.3. What is the text?A.A notice. B.An oral folktale.C.A scientific paper. D.An advertisement.If there’s one thing I’ve realized since becoming a male college student, it’s that finding a summer job is nearly impossible. I’ve applied to so many places and I’ve experienced so many interviews, but I always either get straight-up refusal or never hear from the company again.One time, I even called one of the companies multiple times, but the manager avoided me. I was close to giving up. I felt like I was the only one struggling hard. I had a pretty good resume, and I always dressed nicely for my interviews, so why couldn’t I get a job?Well, the reason is actually right in front of me—I am a student. Companies generally want students who can work all year long, but most of them aren’t willing to be flexible with schedules. I couldn’t tell you how many times interviewers told me that they were looking for someone permanent.I tried looking for jobs marked as temporary ones. And I even once tried to apply through a temporary agency. But it didn’t work. Even if I wanted to work during the school year, none of the companies wanted to hire me because of my limited weekday availability. And despite not knowing if I could juggle (尽量兼顾) both school and a job, I even started to tell interviewers that I would like to work during the school year and give up my weekends. But I had no luck.I’m not sure if there are others like me out there. But if you are going through something similar, what I want to tell you is to keep on trying. Despite being rejected so many times, I still applied for any job that I was qualified for. I even started my job search before the semester ended to get ahead. Eventually, I got my ideal summer job.I know it’s frustrating, and you may feel like you’ve tried everything—that’s how I’ve felt for a long time. And now, with companies requiring years of exp erience, it’s even harder to get a job if you’re someone like me. But don’t give up. Keep searching and applying, sign up for sites that send you job offers and look on the university’s website for on-campus jobs.4. What does the author want to convey in paragraph 2?A.His brilliant academic records.B.The cause of his unemployment.C.His jobless confusion in summer.D.The social prejudice to graduates.5. Why did the temporary agency fail the author?A.He was troubled with schoolwork.B.He was thought to have tight work time.C.He was unwilling to balance study and work.D.He was regarded as an inexperienced student.6. What can be concluded from paragraph 5?A.Well begun is half done.B.Actions speak louder than words.C.Everything comes to him who waits.D.All work and no play makes Jack a dull boy.7. What is the author’s main purpose in writing the last paragraph?A.To give advice. B.To correct an error.C.To compare occupations. D.To recall regrettable experiences.By experiencing the sensations of the reality around us, we create a subjective understanding of what reality is. Language came into being with the development of mankind. It requires the use of more than one of the basic five human senses, which shows that language is a complex process that brings huge power along with it. This power is so strong that it can demonstrate that language can influence the way we think. Language can be an amazing tool for change, both positive and negative.Language can completely change our perception of time. The changed perception of time isn’t the only way language affects how we think. Our sense of self is also significantly changed, especially if a person is bilingual (双语的). Depending on which language a person who is bilingual is using, his sense of self changes. The differences may even become so great as to change his personalities.Word teaching plays an important part in education, so to expand language is to expand the ability to think. We can see this in children, whose thinking develops hand in hand with language. It helps a great deal to increase their “word power” by learning new words in order to develop new ideas and new ways of thinking.The increase in “word power” extends to those who lack the sense of hearing, thanks to t he modern invention of sign language. Since the beginning, sign language has allowed deaf people to become fully literate. Whether we are deaf or not, language transforms experience and connects us to the past as well as the future. Be mindful of how important language is to our perception of reality and all its various aspects, and we can empower ourselves beyond our present limitations and expand our awareness.8. What is the relationship between language and senses?A.Opposite. B.Correlative. C.Independent. D.Competitive.9. What does paragraph 2 highlight about language?A.Its role. B.Its formation.C.Its changes. D.Its differences.10. How can children’s thinking ability be developed according to the text?A.By enlarging their vocabulary.B.By learning about their limitations.C.By changing their ways of speaking.D.By transforming their past experiences.11. Which of the following is the best title for the text?A.Why Does Language Connect Us Closely?B.When Should We Achieve Language Skills?C.How Does Language Influence Our Thoughts?D.What Should We Do to Learn Language Well?A team of physicists at the University of Edinburgh, working with an infection and immunity specialist, has, via experimentation, validated a theory to explain why paint dries at the same rate regardless of humidity (湿度) levels.Generally, paint should dry faster on an outdoor fence on a dry day than when it is humid because evaporation (蒸发) occurs faster when the air around a liquid source is drier. But evidence suggests this is not the case for paint and some other liquids. Chemist Salmon and his colleagues developed a theory to explain why. They suggested it is because large molecules in the liquid are pulled to the surface during evaporation, forming a “polarization layer” that prevents evaporation, and by extension, drying. In this new effort, the research team worked to test this theory.The researchers drilled five holes into a short cylinder (圆柱体) and inserted glass tubes in a horizontal position — each was then sealed in place. They then added a quantity of PVA, a kind of chemical substance, into the cylinder, which they placed on a scale. They poured a thin layer of oil on top of the liquid to prevent surface evaporation. The final touch involved placing an air flow box over the top of the cylinder to allow for controlling humidity levels. The team then ran multiple 17-hour trials to determine evaporation rates, using the scale to measure how much liquid evaporated from the tubes at different humidity levels, ranging from 25% to 90%.The researchers found that as expected, evaporation rates remained constant for approximately three hours. But then, rates plummeted, as was theorized by Salmon, regardless of humidity levels. The evaporation rate didn’t decrea se as humidity increased during the initial three hours. However, the theory only appeared to hold for humidity levels up to 80% — at rates higher than that, evaporation did slow down, which the team suggested was likely due to some other forces.The researchers suggested their work could have medical applications as recent research efforts have shown that respiratory droplets (呼吸道飞沫) tend to form skins similar to those seen in the experimental equipment.12. What is Salmon’s theory aimed at proving?A.The link between evaporation and drying time.B.The connection between humidity and dryness.C.The structure of the “polarization layer” on paint.D.The impact of humidity on the drying rate of paint.13. What is paragraph 3 mainly about?A.The test result. B.The post-test evaluation.C.The research prediction. D.The experimental process.14. What does the underlined word “plummeted” in paragraph 4 mean?A.Fell. B.Kept. C.Disappeared. D.Accelerated. 15. How do the researchers find the study?A.It is tentative. B.It is effortless.C.It is promising. D.It is controversial.You know you really want to get good grades.Your parents have put the pressure on you, or you’ve promised that you’ll do better. 16 If you work to find a focused mindset and establish a study schedule, you can cut out the distractions you have control over and minimize the ones you can’t stop completely.Tune out specific distractions as you notice them. Say you’re trying to study in the library and you keep getting distracted by someone texting. Take note of this specific distraction and then tell yourself you’re going to overcome it. 17 And eventually you’ll no longer notice it.Give yourself a break. 18 So it’s no surprise if you find yourself distracted from study ing by thoughts about a lot of other things. Rather than acting like all of those other needs don’t exist, give yourself an outlet.Spend five minutes thinking about everything that is on your plate, but then tell yourself that it’s time to focus on the mai n task — studying.Prioritize your studying by setting a main goal.When you’ve got an exam coming up, it’s easy to think you need to study everything. If you want to make things more manageable and be less prone to becoming distracted, do as follows: 1920 Some people imagine that knocking out several things at once means you can workfaster.However, doing your homework while watching TV or shopping online will cause you to lose your focus. So concentrate on a piece of work at a time instead.If you fol low the above consistently, you’ll find that you gradually spend less and less time being distracted.Brina Garcia is no stranger to her neighbors. She lives in an apartment and has become quite_________ to two little girls who live nearby, especially after a recent accident that nearly left her apartment in _________. That happened while Brina was away at work.A pot on the stove caught her dog’s _________.It seemed that her dog, Teddy, noticed the pot and _________ to use his paw to turn the stove on. _________, a fire started, prompting the fire alarm to _________. Fortunately, Brina’s young_________, showed up in time when hearing the alarm sound. The girls confirmed that it came from Brina’s apartment and then called 911.Thanks to Brina’s Ring camera, they got in _________ with her. Brina could hear the alarm, urging her to ask the girls if they smelt smoke. They answered with nervous _________, “We did!” Soon after, firefighters arrived.Upon opening the door, the firefighters noticed the high flames, and Brina started to have a breakdown. Thankfully, __________, a video captured this moments.It showed Teddy making an __________, something that might not have happened had it not been for the girls always__________ to others.To show her __________ for the girls’ assistance, Brina planned to reward them with toys and fun treats. “These two little girls always come to my door to see my dog, Teddy,” Brina said. “If it weren’t for them, the firefighters wouldn’t have come to __________ in time, my plac e would be burned down, and my dog would get burned.I’m thankful for my Ring door bell __________ this all on camera.”21.A.close B.obedient C.blind D.offensive22.A.order B.rent C.ruins D.efforts23.A.look B.start C.breath D.eye24.A.pretended B.managed C.continued D.failed25.A.Recently B.Generally C.Previously D.Consequently26.A.go off B.leave off C.break down D.blow up27.A.players B.neighbors C.colleagues D.partners28.A.harmony B.peace C.contact D.line29.A.tension B.excitement C.merriness D.ease30.A.otherwise B.though C.besides D.therefore31.A.appointment B.attempt C.exception D.escape32.A.identical B.prejudicial C.accommodating D.alarming33.A.respect B.support C.sympathy D.appreciation34.A.help B.ask C.register D.investigate35.A.copying B.losing C.recording D.deleting阅读下面短文,在空白处填入1个适当的单词或括号内单词的正确形式。