安庆市第一中学简介
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安徽省安庆市第一中学2022-2023学年高二下学期第一次月考数学试题学校:___________姓名:___________班级:___________考号:___________一、单选题1.设()*211111N 123n a n n n n n n=++∈+++,则2a 等于()A .14B .1123+C .111234++D .11112345+++2.已知各项均为正数的等比数列{}n a 的前4项和为15,且53134a a a =+,则3a =A .16B .8C .4D .23.若命题()()*A n n N ∈在()*n k k N =∈时命题成立,则有1n k =+时命题成立,现知命题对()*00n n n N=∈时命题成立,则有().A .命题对所有正整数都成立B .命题对小于0n 的正整数不成立,对大于或等于0n 的正整数都成立C .命题对小于0n 的正整数成立与否不能确定,对大于或等于0n 的正整数都成立D .以上说法都不正确4.我国古代著作《庄子·天下篇》引用过一句话:“一尺之棰,日取其半,万世不竭.”其含义是:一尺长的木棍,每天截去它的一半,永远也截不完.在这个问题中,记第n 天后剩余木棍的长度为n a ,数列{}n a 的前n 项和为n S ,则使得不等式6164n S >成立的正整数n 的最小值为().A .6B .5C .4D .35.已知正项等比数列{an }满足6856846832a a a =+,若存在两项m a ,n a ,12a =,则14m n+的最小值为()A .9B .73C .94D .1336.已知数列{}n a 的前n 项和122n n S +=-,若*n ∀∈N ,24n n a S λ≤+恒成立,则实数λ的最大值是()A .3B .4C .5D .67.等差数列{}n a 满足:10a >,31047a a =.记12n n n n a a a b ++=,当数列{}n b 的前n 项和n S 取最大值时,n =A .17B .18C .19D .208.“提丢斯数列”,是由18世纪德国数学家提丢斯给出,具体如下:0,3,6,12,24,48,96,192,…,容易发现,从第3项开始,每一项是前一项的2倍;将每一项加上4得到一个数列:4,7,10,16,28,52,100,196,…;再将每一项除以10后得到:“提丢斯数列”:0.4,0.7,1.0,1.6,2.8,5.2,10.0,…,则下列说法中,正确的是()A .“提丢斯数列”是等比数列B .“提丢斯数列”的第99项为9832410⋅+C .“提丢斯数列”前31项和为30321012110⋅+D .“提丢斯数列”中,不超过20的有9项二、多选题9.(多选题)已知三角形的三边构成等比数列,它们的公比为q ,则q 可能的一个值是()A .52B .32C .34D .1210.记n S 为等差数列{}n a 的前n 项和.已知535S =,411a =,则()A .45n a n =-B .23n a n =+C .223n S n n=-D .24n S n n=+11.(多选题)已知等比数列{}n a 的公比23q =-,等差数列{}n b 的首项112b =,若99a b >且1010a b >,则以下结论正确的有()A .9100a a ⋅<B .910a a >C .100b >D .910b b >12.设{}n a 是无穷数列,若存在正整数k ,使得对任意*N n ∈,均有n k n a a +>,则称{}n a 是间隔递增数列,k 是{}n a 的间隔数,下列说法正确的是()A .公比大于1的等比数列一定是间隔递增数列B .已知4n a n n=+,则{}n a 是间隔递增数列C .已知2(1)nn a n =+-,则{}n a 是间隔递增数列且最小间隔数是2D .已知22022n a n tn =-+,若{}n a 是间隔递增数列且最小间隔数是3,则45t ≤<三、填空题13,…,则________项.14.已知数列{}n a 的前n 项和23nn S =-,则数列{}n a 的通项公式是______.15.如图,第n 个图形是由正2n +边形扩展而来的,则第2n -个图形中共有______个顶点.16.设等差数列{}n a 的前n 项和为n S ,若376,28S S ==,则14nn a a S ++的最大值是__四、解答题17.在数列{}n a 中,11a =,13n n a a +=.(1)求{}n a 的通项公式;(2)数列{}n b 是等差数列,n S 为{}n b 前n 项和,若1123b a a a =++,33b a =,求n S .18.已知{}n a 为等差数列,{}n b 为等比数列,()()115435431,5,4a b a a a b b b ===-=-.(Ⅰ)求{}n a 和{}n b 的通项公式;(Ⅱ)记{}n a 的前n 项和为n S ,求证:()2*21n n n S S S n ++<∈N ;(Ⅲ)对任意的正整数n ,设()21132,,,.n nn n n n n a b n a a c a n b +-+⎧-⎪⎪=⎨⎪⎪⎩为奇数为偶数求数列{}n c 的前2n 项和.19.已知数列{}n a 的前n 项和为n S ,且()22n n S a n N *=-∈(1)求数列{}n a 的通项公式;(2)若21log nn na b a +=,求数列{}n b 的前n 项和n T .20.已知函数()f x 满足()()()f x y f x f y +=⋅且1(1)2f =.(1)当*n N ∈时,求()f n 的表达式;(2)设*()n a n f n n N =⋅∈,,求证:1232n a a a a +++⋯+<;21.已知等差数列{}n a 的公差为()0d d ≠,前n 项和为n S ,且满足___________(从①()101051S a =+﹔②1a ,2a ,6a 成等比数列;③535S =,这三个条件中任选两个补充到题干中的横线位置,并根据你的选择解决问题).(1)求n a ﹔(2)设11n n n b a a +=,数列{}n b 的前n 项和为n T ,求证:13n T <.22.习近平总书记指出:“我们既要绿水青山,也要金山银山.”新能源汽车环保、节能,以电代油,减少排放,既符合我国的国情,也代表了世界汽车产业发展的方向.工业部表示,到2025年中国的汽车总销量将达到3500万辆,并希望新能源汽车至少占总销量的五分之一.山东某新能源公司年初购入一批新能源汽车充电桩,每台12800元,第一年每台设备的维修保养费用为1000元,以后每年增加400元,每台充电桩每年可给公司收益6400元.(15.7≈)(2)每台充电桩在第几年时,年平均利润最大.参考答案:1.C【分析】由已知通项公式,令2n =写出2a 即可.【详解】()*211111N 123n a n n n n n n=++++⋯+∈+++ ,2111234a ∴=++.故选:C.2.C【解析】利用方程思想列出关于1,a q 的方程组,求出1,a q ,再利用通项公式即可求得3a 的值.【详解】设正数的等比数列{an }的公比为q ,则2311114211115,34a a q a q a q a q a q a ⎧+++=⎨=+⎩,解得11,2a q =⎧⎨=⎩,2314a a q ∴==,故选C .【点睛】本题利用方程思想求解数列的基本量,熟练应用公式是解题的关键.3.C【详解】由已知可得00(*)n n n =∈N 时命题成立,则有01n n =+时命题成立,在01n n =+时命题成立的前提下,可推得0(1)1n n =++时命题也成立,以此类推可知命题对大于或等于0n 的正整数都成立,但命题对小于0n 的正整数成立与否不能确定.本题选择C 选项.4.B【解析】将问题转化为等比数列求和问题,利用等比数列求和公式求得n S ,解不等式求得结果.【详解】由题意可知:数列{}n a 是以12为首项,12为公比的等比数列,11112211212n n n S ⎛⎫- ⎪⎝⎭∴==--,若6164n S >,则1611264n ->,即31642n >,6423n ∴>,又n N *∈,4642163=<,5642323=>,∴使得不等式6164n S >成立的正整数n 的最小值为5.故选:B.5.B【分析】利用等比数列的通项公式求出公比q 及m 与n 的关系式4m n +=,由于*,N m n ∈,所以采取逐一代入法求解最值即可.【详解】依题意,正项等比数列{an }满足6856846832a a a =+,所以6846836821112a qa q a q =+,即220q q --=,解得q =2或q =-1.因为数列{an }是正项等比数列,所以2q =,所以11·2n n a a -=.12a =,所以4m n +=,且*,N m n ∈,当m =1,n =3时,1473m n +=,当m =n =2时,1452m n +=,当m =3,n =1时,14133m n +=,则14m n +的最小值为73.故选:B .6.C【解析】先由n S 求出n a ,根据24n n a S λ≤+得到24n nS a λ+≤,求出24nn S a +的最小值,即可得出结果.【详解】因为数列{}n a 的前n 项和122n n S +=-,当2n ≥时,()()1122222n n nn n n a S S +-=-=---=;当1n =时,211222a S ==-=满足上式,所以2n n a =()*n N ∈,又*n ∀∈N ,24n n a S λ≤+恒成立,所以*n ∀∈N ,24nnS a λ+≤恒成立;令22121142222222224n n n n n n n n nS b a ++++-+====++,则211112212220222n n n n n n n n b b +++++⎛⎫⎛⎫-=+-+=-> ⎪⎝⎭⎝⎭对任意*n ∈N ,显然都成立,所以1222n n n b +=+单调递增,因此()21min 2252n b b ==+=,即24n n S a +的最小值为5,所以5λ≤,即实数λ的最大值是5.故选:C【点睛】思路点睛:根据数列不等式恒成立求参数时,一般需要分离参数,构造新数列,根据新数列的通项公式,判断其单调性,求出最值,即可求出参数范围(或最值).7.C【解析】根据已知条件求得1,a d 的关系,由此求得n b 的表达式,根据判断n b 的符号,由此求得数列{}n b 的前n 项和n S 取最大值时n 的值.【详解】设等差数列{}n a 的公差为d ,依题意10a >,31047a a =,则()()114279a d a d +=+,即1550,03a d d =-><.所以数列{}n a 的通项公式为()()155581133n a a n d d n d dn d =+-=-+-⋅=-.所以12n n n n b a a a ++=585552333dn d dn d dn d ⎛⎫⎛⎫⎛⎫=-⋅-⋅- ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭3585552333d n n n ⎛⎫⎛⎫⎛⎫=⋅-⋅-⋅- ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭.由于30d <,所以当117n ≤≤时,35855520333d n n n ⎛⎫⎛⎫⎛⎫⋅-⋅-⋅-> ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭,当33185855528181818033327b d d ⎛⎫⎛⎫⎛⎫=⋅-⋅-⋅-=⋅< ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭,331958555210191919033327b d d ⎛⎫⎛⎫⎛⎫=⋅-⋅-⋅-=-⋅> ⎪ ⎪⎝⎭⎝⎭⎝⎭,当20n ≥时,35855520333d n n n ⎛⎫⎛⎫⎛⎫⋅-⋅-⋅-< ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭.由于318192027b b d +=->,所以当19n =时,n S 取得最大值.故选:C【点睛】本小题主要考查等差数列通项公式的基本量计算,考查分析、思考与解决问题的能力,属于中档题.8.C【分析】根据已知定义,结合等比数列的通项公式、前n 项和公式进行判断即可.【详解】记“提丢斯数列”为数列{}n a ,则当3n ≥时,310462n n a --=⋅,解得232410n n a -⋅+=,当2n =时,20.7a =,符合该式,当1n =时,10.550.4a =≠,故20.4,1324,2,10n n n a n n N -*=⎧⎪=⎨⋅+≥∈⎪⎩,故A 错误,而979932410a ⋅+=,故B 错误;“提丢斯数列”前31项和为()3002923232121223051051010⋅++⋅⋅⋅++⨯=+,故C 正确;令23242010n -⋅+≤,则219623n -≤,故2,3,4,5,6,7,8n =,而120a <,故不超过20的有8项,故D 错误,故选:C 9.BC【分析】由题意可设三角形的三边分别为aq,a ,aq (aq ≠0),再对q 分类讨论,解不等式即得解.【详解】解:由题意可设三角形的三边分别为aq,a ,aq (aq ≠0).因为三角形的两边之和大于第三边,①当q >1时,a q +a >aq ,即q 2-q -1<0,解得1<q;②当0<q <1时,a +aq >a q ,即q 2+q -1>0,解得12-+<q <1.综上,q 的取值范围是1(2-+∪,则可能的值是32与34.故选:BC 10.AC【分析】由535S =求出37a =,再由411a =可得公差为434d a a =-=,从而可求得其通项公式和前n 项和公式【详解】由题可知,53535S a ==,即37a =,所以等差数列{}n a 的公差434d a a =-=,所以()4445n a a n d n =+-=-,()2451232n n nS n n --==-.故选:AC.【点睛】本题考查等差数列,考查运算求解能力.11.AD【分析】根据等比数列{}n a 的公比203q =-<,可知9100a a ⋅<,A 正确;由于不确定9a 和10a 的正负,所以不能确定9a 和10a 的大小关系;根据题意可知等差数列{}nb 的公差为负,所以可判断出C 不正确,D 正确.【详解】对A , 等比数列{}n a 的公比23q =-,9a ∴和10a 异号,9100a a ∴<,故A 正确;对B ,因为不确定9a 和10a 的正负,所以不能确定9a 和10a 的大小关系,故B 不正确;对C D ,9a 和10a 异号,且99a b >且1010a b >,9b ∴和10b 中至少有一个数是负数,又1120b => ,0d ∴<910b b ∴>,故D 正确,10b ∴一定是负数,即100b <,故C 不正确.故选:AD.12.BCD【分析】设等比数列{}n a 的公比为(1)q q >,则11(1)n kn k n a a a q q -+-=-,当10a <时,n k n a a +<,可判断A ;24()n kn n kn a a k n k n++--=⋅+,令24()f n n kn =+-,利用其单调性可判断B ;]21()[(1)1n k n k n a a k +-=-⋅+--,分n 为奇数、偶数两种情况讨论可判断C ;若{}n a 是间隔递增数列且最小间隔数是3,则22)0(n k n a a k n t k +-=+->,*N n ∈成立,问题转化为对于22)2(2()0k n t k k t k +-≥+->,存在3k ≥使之成立,且对于20()2k t k +-≤,存在2k ≤使之成立,求解可判断D .【详解】设等比数列{}n a 的公比为(1)q q >,则111111()1n k n n k n k n a a a qa q a q q +---+-=-=-.因为1q >,所以当10a <时,n k n a a +<,故A 错误;244441()()n kn n kn a a n k n kk n k n n k n n k n +⎛⎫+-⎛⎫-=++-+=-=⋅⎪ ⎪+++⎝⎭⎝⎭,令24()f n n kn =+-,则()y f n =在*N n ∈上单调递增,令0(1)14f k =+->,解得3k >,此时0())1(f n f ≥>,n k n a a +>,故B 正确;()()[()]21212111]()[()n k n n k n k n a a n k n k ++-=++--+-⋅-=+--,当n 为奇数时,2()11kn k n a a k +-=--+,存在1k ≥,使0n k n a a +->成立;当n 为偶数时,2()11kn k n a a k +-=+--,存在2k ≥,使0n k n a a +->成立.综上{}n a 是间隔递增数列且最小间隔数是2,故C 正确;若{}n a 是间隔递增数列且最小间隔数是3,则2222()202202220()()()n k n a a n k t n k n tn k n t k +-=+-++--+=+->,*N n ∈成立,则对于22)2(2()0k n t k k t k +-≥+->,存在3k ≥使之成立,且对于20()2k t k +-≤,存在2k ≤使之成立.即对于(2)0k t +->,存在3k ≥使之成立,且对于0()2k t +-≤,存在2k ≤使之成立,所以23t -<,且22t -≥,解得45t ≤<,故D 正确.故选:BCD.13.7【分析】根据题中所给的数据,推出数列的通项公式,即可得出答案.【详解】解:∵1a =2a =3a =4a =n a =.=3n -1=20⇒n =7,∴7项.故答案为:7.14.1112,2n n n a n --=⎧=⎨≥⎩,【分析】根据21n n S =-求出首项、第二项,从而得出公比,从而求出数列{}n a 的通项公式.【详解】解:当1n =时,111231a S ==-=-,所以11a =-,当2n =时,2212231a a S +==-=,即得到22a =,因为23n n S =-①,所以当2n ≥时,1123n n S --=-②,①-②得()()11123232n n n n n n a S S ---=-=---=,当1n =时,11121a -==不满足11a =-,所以1112,2n n n a n --=⎧=⎨≥⎩,,故答案为:1112,2n n n a n --=⎧=⎨≥⎩,.【点睛】本题考查由数列的前n 项和求数列的通项公式,注意验证1n =的情况,属于中档题.15.()1n n +【分析】由n 边形有n 个顶点及图形的生成规律确定.【详解】由题意第2n -个图形是由n 边形的每边中间向外扩展n 边形得到,顶点数为2(1)n n n n +=+.故答案为:(1)n n +.16.17【分析】根据题意求得n a n =及4(4)(5)2n n n S +++=,化简14212(1)71n n a a S n n ++=++++,结合基本不等式,即可求解.【详解】设等差数列{}n a 的公差为d ,因为376,28S S ==,可得1133672128a d a d +=⎧⎨+=⎩,解得11,1a d ==,所以n a n =,所以4(4)(14)(4)(5)22n n n n n S ++++++==,则141221(4)(5)12127(1)747214n n a a n n n S n n +++==≤=++++++++,当且仅当3n =时,等号成立,所以14n n a a S ++的最大值是17.故答案为:17.17.(1)13n n a -=;(2)214n n -+.【分析】(1)由等比数列的定义可知数列{}n a 是首项为1,公比为3的等比数列,则{}n a 的通项公式易求;(2)由(1)得:1313,19b b ==,由此求得公差d ,代入等差数列前n 公式计算即可.【详解】(1)因为111,3n na a a +==所以数列{}n a 是首项为1,公比为3的等比数列,所以13n n a -=.(2)由(1)得:1123313913,19b a a a b =++=++==,则3124,2b b d d -==-=-,,所以()()21132142n n n n S n S n n +=+⨯-⇒=-+.【点睛】本题考查等差数列,等比数列的基本量计算,属基础题.18.(Ⅰ)n a n =,12n n b -=;(Ⅱ)证明见解析;(Ⅲ)465421949n n n n +--+⨯.【分析】(Ⅰ)由题意分别求得数列的公差、公比,然后利用等差、等比数列的通项公式得到结果;(Ⅱ)利用(Ⅰ)的结论首先求得数列{}n a 前n 项和,然后利用作差法证明即可;(Ⅲ)分类讨论n 为奇数和偶数时数列的通项公式,然后分别利用指数型裂项求和和错位相减求和计算211n k k c -=∑和21nk k c =∑的值,据此进一步计算数列{}n c 的前2n 项和即可.【详解】(Ⅰ)设等差数列{}n a 的公差为d ,等比数列{}n b 的公比为q .由11a =,()5435a a a =-,可得d =1.从而{}n a 的通项公式为n a n =.由()15431,4b b b b ==-,又q ≠0,可得2440q q -+=,解得q =2,从而{}n b 的通项公式为12n n b -=.(Ⅱ)证明:由(Ⅰ)可得(1)2n n n S +=,故21(1)(2)(3)4n n S S n n n n +=+++,()()22211124n S n n +=++,从而2211(1)(2)02n n n S S S n n ++-=-++<,所以221n n n S S S ++<.(Ⅲ)当n 为奇数时,()111232(32)222(2)2n n n n n n n n a b n c a a n n n n-+-+--==-++,当n 为偶数时,1112n n n n a n c b -+-==,对任意的正整数n ,有222221112221212121k k nn n k k k c k k n --==⎛⎫=-=- ⎪+-+⎝⎭∑∑,和223111211352321444444n n k k n n k k k n n c -==---==+++++∑∑ ①由①得22314111352321444444n k n n k n n c +=--=+++++∑ ②由①②得22111211312221121441444444414n n k n n n k n n c ++=⎛⎫- ⎪--⎝⎭=+++-=---∑ ,由于11211121221121156544144334444123414n n n n n n n n ++⎛⎫- ⎪--+⎝⎭--=-⨯-⨯=-⨯-,从而得:21565994n k n k n c =+=-⨯∑.因此,2212111465421949n n n n k k k n k k k n c c c n -===+=+=--+⨯∑∑∑.所以,数列{}n c 的前2n 项和为465421949n n n n +--+⨯.【点睛】本题主要考查数列通项公式的求解,分组求和法,指数型裂项求和,错位相减求和等,属于中等题.19.(1)2nn a =(2)332n nn T +=-【分析】(1)根据11,1,2,N n nn S n a S S n n -=⎧=⎨-≥∈⎩,再结合等比数列的定义,即可求出结果;(2)由(1)可知12n nn b +=,再利用错位相减法,即可求出结果.【详解】(1)解:因为22n n S a =-,当1n =时,1122S a =-,解得12a =当2n ≥时,1122n n S a --=-,所以()()111222222n n n n n n n a S S a a a a ---=-=---=-,即12(2)n n a a n -=≥.所以数列{}n a 是首项为2,公比为2的等比数列.故1222n n n a -=⨯=.(2)解:由(1)知2nn a =,则221log 1log 2122n n n n n n a n b a +++===,所以2323412222n n n T +=++++L ①231123122222n n n n n T ++=++++ ②,①-②得23111111122222n n n n T ++⎛⎫=++++- ⎝⎭L 21111112211212n n n -+⎛⎫- ⎪+⎝⎭=+--1111133122222n n n n n ++++=+--=-.所以数列{}n b 的前n 项和332n n n T +=-20.(1)()*1()2n f n n ⎛⎫=∈ ⎪⎝⎭N ;(2)详见解析.【分析】(1)令1y =,将函数表示为等比数列,根据等比数列公式得到答案.(2)将n a 表示出来,利用错位相减法得到前N 项和,最后证明不等式.【详解】(1)令1y =,得()()()11f x f x f +=⋅,∴()()()11f n f n f +=⋅,即()()()()*111,22n f n f n n N f n +⎛⎫=∴=∈ ⎪⎝⎭(2)12n n a n ⎛⎫=⋅ ⎪⎝⎭,设121n a n n T a a a a a -=+++⋯++,则()23111111123122223n n n T n n -⎛⎫⎛⎫⎛⎫⎛⎫=⋅+⋅+⋅++-+⋅ ⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭⎝⎭ ,①()()23111111111221322322n n n n T n n n -+⎛⎫⎛⎫⎛⎫⎛⎫⎛⎫=⋅+⋅++-+-+⋅ ⎪ ⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭⎝⎭⎝⎭ ,②来①-②得11122n n ⎛⎫⎛⎫=-+⋅ ⎪ ⎪⎝⎭⎝⎭,23111111221111111112222222212n n n n n n T n n -++⎡⎤⎛⎫-⎢⎥ ⎪⎝⎭⎢⎥⎛⎫⎛⎫⎛⎫⎛⎫⎛⎫⎛⎫⎣⎦=+++++-⋅=-⋅ ⎪ ⎪ ⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭⎝⎭⎝⎭⎝⎭- ()12222n n T n ⎛⎫∴=-+⋅< ⎪⎝⎭【点睛】本题考查了函数与数列的关系,错位相减法,综合性强,意在考查学生的计算能力和综合应用能力.21.条件选择见解析;(1)32n a n =-;(2)证明见解析.【解析】(1)由①可得11a =,由②可得13d a =,由③可得3127a a d =+=,选择①②、①③、②③条件组合,均得11a =,3d =,即得解析式;(2)可得11133231n b n n ⎛⎫=- -+⎝⎭,由裂项相消法求出n T 即可证明.【详解】(1)①由()101051S a =+,得()11109105912a d a d ⨯+=++,即11a =;②由1a ,2a ,6a 成等比数列,得2216a a a =,222111125a a d d a a d ++=+,即13d a =;③由535S =,得()15355352a a a +==,即3127a a d =+=;选择①②、①③、②③条件组合,均得11a =,3d =,故()13132n a n n =+-=-.(2)()()111111323133231n n n b a a n n n n +⎛⎫===- ⎪-+-+⎝⎭∴123n nT b b b b =++++ 11111111134477103231n n ⎡⎤⎛⎫⎛⎫⎛⎫⎛⎫=-+-+-++- ⎪ ⎪ ⎪ ⎪⎢⎥-+⎝⎭⎝⎭⎝⎭⎝⎭⎣⎦L 111331n ⎛⎫=- ⎪+⎝⎭,∵n *∈N ,∴1031n >+,∴13n T <.【点睛】方法点睛:数列求和的常用方法:(1)对于等差等比数列,利用公式法可直接求解;(2)对于{}n n a b 结构,其中{}n a 是等差数列,{}n b 是等比数列,用错位相减法求和;(3)对于{}+n n a b 结构,利用分组求和法;(4)对于11n n a a +⎧⎫⎨⎩⎭结构,其中{}n a 是等差数列,公差为d ,则111111n n nn a a d a a ++⎛⎫=- ⎪⎝⎭,利用裂项相消法求和.22.(1)公司从第3年开始获利;(2)在第8年时,每台充电桩年平均利润最大【分析】(1)由题意知每年的维修保养费用是以1000为首项,400为公差的等差数列,由此可得第n 年时累计利润的解析式()6400[10001400(400600)]12800f n n n =-++++-L ,则()0f n >,解之即可;(2)每台充电桩年平均利润为()6420028f n n n n ⎛⎫=-+- ⎪⎝⎭,由基本不等式可求出最大值,注意等号成立的条件.【详解】(1)由题意知每年的维修保养费用是以1000为首项,400为公差的等差数列,设第n 年时累计利润为()f n ,()6400[10001400(400600)]12800f n n n =-++++-L 6400(200800)12800n n n =-+-2200560012800n n =-+-()22002864n n =--+,开始获利即()0f n >,∴()220028640n n --+>,即228640n n -+<,解得1414n -<<+5.7≈,∴2.625.4n <<,∴公司从第3年开始获利;(2)每台充电桩年平均利润为()642002828)2400f n n n n ⎛⎫=-+--= ⎪⎝⎭,当且仅当64n n=,即8n =时,等号成立.即在第8年时每台充电桩年平均利润最大为2400元.【点睛】本题考查等差数列的实际应用和利用基本不等式求最值,考查学生分析问题,解决问题的能力,根据条件列出符合题意的表达式是解本题的关键,属中档题.。
安庆一中2021—2022学年第一学期期中考试高二语文试题说明:①本试卷分为两卷,第I卷阅读题66分,第II卷表达题84分,共150分。
考试时间150分钟。
②答案一律答在答题纸指定位置上,答在试卷上无效。
第Ⅰ卷(阅读题共66分)一、(9分)阅读下面的文字,完成1~3题。
不言之美,不是以缄默的方式去体物,不言不是不说话,而是放弃“人之言”,达到“天之言”的境界。
“天之言”乃是不以人的学问去言说,而以生命的本相去呈现。
庄子说:“天地有大美而不言。
”这句话是传统美学不言之美的一个代表性观点。
这句话有三个理论层次:其一,不言之美作为一种“大美”,不与“小美”相对,它是根本的美,是美的本体;其二,天地以“不言’为美的根本特点,美的制造就是归复自然之道,故以“不言”之美为美的最高准则;其三,天地之美并非与人的世界无关,在中国哲学中,天地不是纯然外在的物质世界,它是人的生命所映照的世界。
《庄子》一书共使用“美”52次,其中多处含有哲学意义。
它将美分成两种类型:一是一般的美,这是相对的美;一是道之美,这是确定的美。
前者称其为小美,后者称为大美,或者至美。
前者属于人的理性的视界,是人的语言可以表达的。
而后者不涉人的理性,是人类语言所不行分别的浑然之美,是不言之美。
前者是人为之美,后者为造化之美。
在庄子看来,美是一个自然呈现的世界,美是不行说的,可说则非美。
有言的世界是语言可以描述的世界,语言的有限性打算它无法真实反映这个世界。
所以庄子认为有言之美肯定是有限的、相对的、不完全的、片面的。
而不言之美中,没有外在的审美,有外在的审美,就是生疏,是观照者对对象的生疏,不言之美排解这样的对象存在的可能性。
这样的美只能通过体验妙悟而获得。
在庄子看来,一般美是是学问的判分,是有分别的美;而大美则是超越学问、是无分别的美。
一般美不脱主观性,而主观世界下的美则不是真美。
一般美受制于主体学问的局限,那位因大雨兴奋而跳动的河伯,“以天下之美为尽在己”,这样的美的结论带有虚幻不实性。
考试范围:xxx;满分:***分;考试时间:100分钟;命题人:xxx 学校:__________ 姓名:__________ 班级:__________ 考号:__________一、选择题1.下列现象属于化学变化的是A.汽油挥发B.食物腐烂C.电灯发光D.冰雪融化2.下列物质的用途中,利用了其化学性质的是A.氧气用于医疗急救B.液氮冷藏血液C.铜用作制导线D.黄金用作制首饰3.给试管里的物质加热时,切勿让试管底部接触灯芯,这是因为( )A.将使酒精燃烧不完全B.易使酒精灯熄灭C.灯芯温度低,易使已受热后的试管受热不均匀而破裂D.灯芯温度高,易使试管底部熔化4.下列一定属于化学变化的是()A.冰化成水B.铁水变成铁块C.气球爆炸D.火药爆炸5.下列变化中,发生物理变化的是A.铁钉生锈B.木柴燃烧C.汽油挥发D.米饭变馊6.装置的气密性的检查方法有很多,如可用推拉注射器活塞的方法。
当缓慢推活塞时,如果装置气密性良好,可观察到的现象是A.长颈漏斗下端口产生气泡B.瓶中液面上升C.注射器内有液体D.长颈漏斗内液面上升7.下列典故主要体现化学变化的是()A.凿壁偷光B.火烧赤壁C.铁杵磨成针D.司马光砸缸8.下列实验操作中正确的是A.熄灭酒精灯B.取液体药品C.给液体加热D.读液体的体积9.将鸡蛋放入白醋中,蛋壳表面有很多气泡产生,产生的气体是不是二氧化碳呢?小明提出可以用澄清石灰水来检验,这个环节属于科学探究中的A.提出假设B.设计实验C.交流评价D.得出结论10.下列实验操作规范的是A.两人合作滴加液体B.读取液体体积C.取少量液体D.手按短柄加热液体11.下列实验操作或设计中正确的是A.用100mL量筒量取8.5mL的水B.检测装置气密性C.验证质量守恒定律D.倾倒液体药品二、填空题12.①铁熔化成铁水;②糯米酿成酒;③铁在潮湿的空气中容易生锈;④灯泡中的钨丝通电后发热发光;⑤食物腐烂;⑥木柴燃烧;⑦胆矾是蓝色固体.上述几种情况中(用序号填空):(1)属于描述物理性质的是______,描述化学性质的是______;(2)属于物理变化的是______,属于化学变化的是______.13.如图所示,该液体的体积是 _____mL。
安庆一中2015-2016学年度高一年级第一学期期中考试历史试卷一、选择题(本大题共30小题,每小题2分,共计60分)1.《春秋左传》中记载:“王后无适,则择立长。
年钧以德,德钧以卜。
”(无适:没有嫡子。
钧:均等。
)这段记载说明()A.宗法制下都是按年龄大小来确定继承人B.春秋时期只能靠占卜来解决继承问题C.古代宗法制有一套相对完整的实施办法D.贤德是宗法制确立继承人的首要依据2.有学者认为:“西周的封建社会,从纵剖面看,是一个宝塔式结构,王室之下,有几级的封建,从横切面来看,统治阶级中,也存在着以亲属血缘为基础的宗族组织。
”这说明西周社会在政治上()A.具有家国同构、家国一体的特点B.建立了以血缘关系为基础的中央集权C.宗族组织与政治系统截然分开D.“天下为家”开始取代“天下为公”3.古代中国的政治制度,经历了不断改革、发展和完善的过程,对中国历史发展产生了深远的影响。
以下对古代中国地方行政制度的论述,正确的是()A.分封制既稳定了当时的政治秩序,也蕴含着以后分裂割据的因素B.郡县制是贵族政治取代官僚政治的标志,推动了中央集权制的形成C.行省制是满洲族的重要政治创新,有利于巩固统一的多民族国家D. 隋唐时期地方行政区划始由郡县两级转变成州、郡、县三级制。
4.《汉书·地理志》言:“秦并兼四海,以为周制微弱,终为诸侯所丧,故不立尺土之封,分天下为郡县,荡灭前圣之苗裔,靡有孑遗。
”这说明秦朝采取的制度是()A.皇帝制度B.郡县制C.宗法制D.世袭制5.秦始皇在中央机构中设置太尉一职,但今天留下来的古籍中没有记载秦始皇曾经任命过哪一位人物担任过此职,最可能的原因是()A.太尉辅佐皇帝处理全国政务,皇帝认为其权力重大,不轻易任命B.秦始皇自己直接控制军队,使权力更加集中C.太尉负责监督百官,秦始皇缺乏可以担任此一重任的优秀人才D.秦朝短命而亡,未来得及任命6.某史学家认为:“后世官制,变化繁赜。
安庆初中学校排名,安庆重点初中排名详细榜单
2018年安庆初中学校排名,安庆重点初中排名详细榜单
孩子小升初,几乎所有的家长都会陷入纠结,都想为孩子选择一所“好学校”,在择校过程中,家长们总想知道安庆初中学校排名以及安庆重点初中排名详细榜单,但这里小编提醒一句,家长要根据孩子的实际情况出发,与其选最有名的不如选最适合自己孩子的。
下面小编整理了关于2018年安庆初中学校排名,安庆重点初中排名详细榜单。
排名仅供参考!
大枫初级中学2018年黄山初中学校排名,黄山重点初中排名详细榜单
孩子小升初,几乎所有的家长都会陷入纠结,都想为孩子选择一所“好学校”,在择校过程中,家长们总想知道黄山初中学校排名以及黄山重点初中排名详细榜单,但这里小编提醒一句,家长要根据孩子的实际情况出发,与其选最有名的不如选最适合自己孩子的。
下面小编整理了关于2018年黄山初中学校排名,黄山重点初中排名详细榜单。
排名仅供参考!
黄山区桃源初级中学安庆市第十四中学怀宁县独秀初级中学怀宁县栏坝初中。
安徽省安庆市第一中学2023-2024学年高一上学期12月期中英语试题学校:___________姓名:___________班级:___________考号:___________一、阅读理解The New Jersey State Botanical (植物学的) Garden (NJBG) is a part of Ringwood State Park, New Jersey Division of Parks and Forestry, Department of Environmental Protection. ItRenew Membership1.What’s one of the purposes of the money paid for membership?A.To provide service for the public.B.To build a new botanical museum.C.To improve the educational level of the gardeners.D.To update NJBG’s payment system.2.What benefit does the NJBG members get?A.Joining in activities for free.B.Visiting the Garden anytime.C.Learning to care for a garden.D.Buying plants at a lower price. 3.How much do you need to renew the two-year membership for you and your parents?A.$60.B.$90C.$100.D.$110.The first day of school is a special milestone for any student, but for one family in Wisconsin, it’s extra special. Two sisters Mia and Samantha, their mom Amy and grandmother Christy attended Carthage College together this fall.Amy said, “I’m really proud to be watching my daughters grow up and be more mature and have new experiences, and very happy to see my mom achieve something that she’s always wanting to do.”Mia shared that she always felt her two older role models would return to school someday. To 19-year-old Samantha, her mom and grandmother’s entry to university was rather a surprise. “It was clear that Mia and I were admitted. And then all of a sudden, they were admitted too,” Samantha remembered. “It was really surprising. And I didn’t expect it.”Amy, a mother of five children, has worked at Carthage College for over two decades and wanted to be enrolled one day. Calling herself “Carthage’s biggest fan”, she said she felt like she now had the time to pursue higher studies.As for 71-year-old Christy, she retired three years ago but is still eager to learn. In fact, she still continues to support and volunteer at local nonprofits. Christy said she was also inspired by her son Joshua, who is pursuing his second master’s degree. She has decided to go forward with a master’s degree in business, design and innovation alongside her daughter.The women are inspirational to anyone who doesn’t want their age to block their dreams. Amy advised everyone to go after what they want because life is too short. “Put that doubt aside and just go for it,” she said. Christy added, “Never hesitate to follow your fear. In my life, it has led me to my greatest opportunities and has also built my greatest strengths. If I always stayed in my comfort zone, I wouldn’t be where I am today.”A.All the family members went to the same college.B.Different generations became schoolmates.C.Twin sisters went to college with their father.D.Carthage College Amy and Christy were admitted to is very famous.5.How did Mia feel about her mother and grandmother’s attending college?A.Calm.B.Worried.C.Moved.D.Surprised. 6.What can we know about Christy from paragraph 5?A.She retired at the age of sixty.B.She has five grandchildren in all.C.Her majors are the same as Amy’s.D.Her son graduated from the same college.7.What message does the author want to convey to readers?A.Follow your heart and pursue your dream.B.Many hands make light work.C.Rome was not built in a day.D.There is no royal road to learning.In a world-record effort to help save a valuable sea creature, Australian scientists have released hundreds of baby seahorses into the wild. The tiny seahorses are endangered, and the scientists hope the new seahorses will help their numbers grow.Seahorses get their name because they look a bit like horses. They aren’t great swimmers, even though they’re fish. They often use their tails to hold onto something in the water. They mostly live in warm, shallow waters around the world. They are often found in coral reefs, in beds of seagrass, and areas where rivers empty into the sea. Seahorses form an important part of the ocean’s food chain. They eat tiny sea creatures and are eaten by bigger sea animals.Many kinds of seahorses are often threatened by the human actions. Sometimes they’re caught and sold as pets. They are also caught by accident when people are trying to catch other fish.To begin the project, scientists collected three pregnant seahorses in January. Those seahorses were brought back to the aquarium (水族馆) in Sydney. After the babies were born, the scientists kept them there for five months, feeding the baby seahorses shrimps (小虾) tohave to eat constantly.”About a month before the young seahorses were released, the scientists created eight underwater “hotels” for them. The hotels look like cages, providing a safe place for the seahorses to develop. Putting the hotels into the sea early allowed the cages to be covered with small sea life that can help provide food for the seahorses.This is the fifth time the scientists have released seahorses into the area, and this time was a record. Around 380 seahorses were released. The researchers put tiny tags (标记) under the skin of many of the seahorses to help track them in the future.8.What can be learned about seahorses from paragraph 2?A.They look exactly like horses.B.They have a gift for swimming.C.They mostly live in the deep sea.D.They feed on small sea creatures. 9.What does paragraph 3 mainly talk about?A.The types of the seahorses.B.Living conditions the seahorses need.C.Areas the seahorses live in.D.Dangers the seahorses face.10.Why are the eight “hotels” put into the sea early?A.To differ the project from the former ones.B.To avoid danger the seahorses may face.C.To offer food to the seahorses.D.To help track the seahorses in the future.11.What can be the best title for the text?A.A New Study on Endangered SeahorsesB.Underwater “Hotels” for Baby SeahorsesC.A Record Number of Baby Seahorses Were ReleasedD.New Methods of Finding Endangered SeahorsesSocial media allow teenagers to create online identities, communicate with others and build social networks. These networks can provide teenagers with valuable support. Teenagers also use social media for entertainment and self-expression. And the platforms can expose teenagers to current events, allow them to communicate across geographic barriers and teach them about different kinds of subjects, including healthy behaviors. However, social media use can also negatively affect teenagers, distracting them, influencing their sleep,people’s lives and peer pressure.There are steps you can take to encourage responsible use of social media and limit some of its negative effects.Set reasonable limits. Talk to your teenager about how to avoid letting social media affect his or her activities, sleep, meals or homework. Encourage a bedtime routine that avoids electronic media use, and keep cellphones and iPads out of teenagers’ bedrooms. Set an example by following these rules yourself.Monitor your teenager’s accounts. Let your teenager know that you’ll be regularly checking his or her social media accounts. You might aim to do so once a week or more. And make sure you follow through.Explain what’s not OK. Discourage your teenager from gossiping, spreading rumors, bullying or damaging someone’s reputation—online or otherwise. Talk to your teenager about what is appropriate and safe to share on social media.Encourage face-to-face contact with friends. This is particularly important for teenagers who are vulnerable to social anxiety disorder.Talk about social media. Talk about your own social media habits. Ask your teenager how he or she is using social media and how it makes him or her feel. Remind your teenager that social media is full of unrealistic images.If you think your teenager is experiencing signs or symptoms of anxiety or depression related to social media use, talk to your child’s health care provider immediately.12.How does the author mainly develop the first paragraph?A.By providing reasons.B.By making comparison.C.By following the order of importance.D.By raising questions.13.What’s a better way to avoid being affected by cellphones?A.Powering them off.B.Putting them in the schoolbag.C.Keeping them out of bedroom.D.Listening to them instead of watching. 14.What does the underlined word “vulnerable” in paragraph 6 probably mean?A.Warm-hearted.B.Easily hurt.C.Deeply moved.D.Hard-working. 15.Who is the text written for?A.Teenagers.B.Officials.C.Teachers.D.Parents.travel.When I sit on the bike, I am free and flexible. I can stop at any time to eat or start the stove to enjoy a coffee with breathtaking views. I’m not dependent on bus or train. 17 I come to places I would never have seen. My bike makes it possible for me not to plan beforehand, which leaves space for adventure. Because adventures don’t come around the corner during a planned hotel-vacation.I am in the nature the whole day. The wind blows across my face. 18 I see monkeys hanging directly above me in the tree, whales swimming along the coast, a bear waving at us and many more animals. Smelling the blackberries, I’m stopping to fill my stomach. In the car, bus or train, I would have missed all of these.19 Some long-term cyclists spend 4,000 dollars per year or less. And I spend about 350-450 dollars a month. This is due to two reasons: I have no transport costs. And I also have the freedom of wild camping, during which I can cook for myself. All these factors contribute to a cheap travel.I could tell hundreds of stories. Because of getting to know so many people, I have experienced a lot. The travel form itself invites many to ask questions. And the best thing about it is that all these stories make me rich. I’m rich in memories, of which I always think with laughter. 20A.I listen to the birds singing.B.And they think it’s so tiring.C.It will change the way you see the world.D.I can decide for myself when and where to go.E.Before my start, I was fascinated by the bike touring community.F.Nobody can ever take them away and they are of great value to me.G.Compared to other travel forms, bike touring is one of the most affordable.二、完形填空The piano, ever since its creation, has had a great impact on the world of music. I haveThe easy guess is that I was always so purely in love with 22 and piano that I couldn’t 23 let them go, even though my life got busier. However, I used to 24 a lot with piano. Peers who played the instrument 25 placed me in competition. I felt pressure to improve and be the best to 26 myself. Gradually, my 27 in music was developed in 28 and doubt.It’s 29 to love something that you don’t choose from your heart. I didn’t choose piano; for a while, it was more of a nuisance (讨厌的事物) than a hobby. But somehow, sometime, 30 grew. By high school, I found something that made it worth it for me to 31 for my own connection to the art. And I met teachers who 32 me and helped me turn the nuisance into what I loved. I found confidence not because I got good enough but I learned that anything I had was 33 enough to be loved.The love and hate I’ve had for the piano were 34 and grown; neither existed innately (与生俱来地) nor long-lasting. If you hate something not chosen by yourself, put your devotion to it and love can make a 35 in its place.21.A.raise B.make C.save D.exchange 22.A.singing B.performance C.music D.relaxation 23.A.plan to B.bear to C.refuse to D.expect to 24.A.practice B.compare C.struggle D.gain 25.A.seldom B.hardly C.never D.often 26.A.introduce B.express C.prove D.teach 27.A.interest B.ability C.knowledge D.information 28.A.adventure B.competition C.confidence D.failure 29.A.wise B.natural C.difficult D.strange 30.A.safety B.love C.chance D.trust 31.A.care B.leave C.wait D.fight 32.A.encouraged B.thanked C.ignored D.followed 33.A.simple B.quiet C.expensive D.good 34.A.missed B.weakened C.stopped D.planted 35.A.home B.rule C.wish D.move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。
LIBERAL ARTS FANS2023年第12期教育教学《普通高中语文课程标准(2017年版)》(以下简称“新课标”)指出,为确保全体学生都具备良好的语文素养,要提高教师水平,发展教师特长,引导教师开发语文课程资源,有选择、创造性地实施课程;把握信息时代新特点,积极利用新技术、新手段,打造开放、多样、有序的语文课程体系,使学生语文素养的发展与提升能适应社会进步的需要[1]。
这就要求教师有选择、创造性地实施国家课程,同时从校情、学情出发,推进国家课程校本化,积极开发、整合富有本地特色的语文课程资源,灵活实施高中语文校本课程,提升不同层次学生的语文核心素养。
为深入研究省级课题“基于语文核心素养培养的高中语文校本课程研究”,安庆市第二中学语文课题组成员开发并实施了高中语文校本课程“文学与其他学科的亲缘关系”和“古诗词鉴赏”。
为科学考察安庆市第二中学高中语文校本课程的开发、实施与评价情况,笔者设计了学前调查问卷和学后调查问卷,观摩并录制了两节语文校本课程示范课。
针对校本课程“文学与其他学科的亲缘关系”发放学前和学后调查问卷各30份,分别回收有效问卷30份;针对校本课程“古诗词鉴赏”发放学前和学后调查问卷各40份,分别回收有效问卷40份。
现结合本次调查问卷结果和校本课程课堂教学情况进行深入分析,总结成功经验,分析存在的问题,反思其中的不足,为制定一套具有我校特色的基于语文学科核心素养培养的高中语文校本课程开发、实施和评价的规划方案提供依据与参考。
一、科学开发是前提(一)充分考虑校情、学情高中语文校本课程不同于国家课程,是国家课程的重要补充,应该立足于校情和学情,兼顾地方特色和学校特色,真正做到“以校为本”。
安庆市第二中学是安徽省示范高中,也是安徽省新课程改革试验样本学校,学校每年招收的高中生源质量整体较好,在市区仅次于安庆市第一中学,但由于近几年每年招生数量在800人左右,其中又包含许多定向指标,定向招生的对象没有分数门槛限制,导致学生进校时的学习水平参差不齐。