苏州市2018届高三上学期期中考试数学试题(完整资料).doc

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江苏省苏州市2018届高三数学期中调研试题

江苏省苏州市2018届高三数学期中调研试题

2017—2018学年第一学期高三期中调研试卷数 学注意事项:1.本试卷共4页.满分160分,考试时间120分钟.2.请将填空题的答案和解答题的解题过程写在答题卷上,在本试卷上答题无效. 3.答题前,务必将自己的姓名、学校、准考证号写在答题纸的密封线内.一、填空题(本大题共14小题,每小题5分,共70分,请把答案直接填写在答卷纸...相应的位置)1.已知集合{1,2,3,4,5},{1,3},{2,3}U A B ===,则()U A B =ðI ▲ . 2.函数1ln(1)y x =-的定义域为 ▲ .3.设命题:4p x >;命题2:540q x x -+≥,那么p 是q 的 ▲ 条件(选填“充分不必要”、“必要不充分”、“充要”、“既不充分也不必要”).4.已知幂函数22*()m m y x m -=∈N 在(0,)+∞是增函数,则实数m 的值是 ▲ . 5.已知曲线3()ln f x ax x =+在(1,(1))f 处的切线的斜率为2,则实数a 的值是 ▲ . 6.已知等比数列{}n a 中,32a =,4616a a =,则7935a a a a -=- ▲ .7.函数sin(2)(0)2y x ϕϕπ=+<<图象的一条对称轴是12x π=,则ϕ的值是 ▲ . 8.已知奇函数()f x 在(,0)-∞上单调递减,且(2)0f =,则不等式()01f x x >-的解集为 ▲ .9.已知tan()24απ-=,则cos2α的值是 ▲ .10.若函数8,2()log 5,2ax x f x x x -+⎧=⎨+>⎩≤(01)a a >≠且的值域为[6,)+∞,则实数a 的取值范围是 ▲ .11.已知数列{},{}n n a b 满足1111,1,(*)21n n n n a a b b n a +=+==∈+N ,则122017b b b ⋅⋅=L ▲ .12.设ABC △的内角,,A B C 的对边分别是,,a b c ,D 为AB 的中点,若cos sin b a C c A =+且CD =ABC △面积的最大值是 ▲ .13.已知函数()sin()6f x x π=-,若对任意的实数5[,]62αππ∈--,都存在唯一的实数[0,]m β∈,使()()0f f αβ+=,则实数m 的最小值是 ▲ .14.已知函数l n ,0()21,0x xf x x x >⎧=⎨+⎩≤,若直线y a x =与()y f x =交于三个不同的点(,()),(,(A m f m B n f n(,())C t f t (其中m n t <<),则12n m++的取值范围是 ▲ . 二、解答题(本大题共6个小题,共90分,请在答题卷区域内作答,解答时应写出文字说明、证明过程或演算步骤) 15.(本题满分14分)已知函数1())(0,0)242f x ax b a b π=+++>>的图象与x 轴相切,且图象上相邻两个最高点之间的距离为2π.(1)求,a b 的值;(2)求()f x 在[0,]4π上的最大值和最小值.16.(本题满分14分)在ABC △中,角A ,B ,C 所对的边分别是a ,b ,c ,已知sin sin sin ()B C m A m +=∈R ,且240a bc -=.(1)当52,4a m ==时,求,b c 的值; (2)若角A 为锐角,求m 的取值范围.17.(本题满分15分)已知数列{}n a 的前n 项和是n S ,且满足11a =,*131()n n S S n +=+∈N . (1)求数列{}n a 的通项公式; (2)在数列{}n b 中,13b =,*11()n n n na b b n a ++-=∈N ,若不等式2n n a b n λ+≤对*n ∈N 有解,求实数λ的取值范围.18.(本题满分15分)如图所示的自动通风设施.该设施的下部ABCD 是等腰梯形,其中AB 为2米,梯形的高为1米,CD 为3米,上部CmD 是个半圆,固定点E 为CD 的中点.MN 是由电脑控制可以上下滑动的伸缩横杆(横杆面积可忽略不计),且滑动过程中始终保持和CD 平行.当MN 位于CD 下方和上方时,通风窗的形状均为矩形MNGH (阴影部分均不通风).(1)设MN 与AB 之间的距离为5(02x x <≤且1)x ≠米,试将通风窗的通风面积S (平方米)表示成关于x 的函数()y S x =;(2)当MN 与AB 之间的距离为多少米时,通风窗的通风面积S 取得最大值?19.(本题满分16分)已知函数2()ln ,()f x x g x x x m ==--. (1)求过点(0,1)P -的()f x 的切线方程;(2)当0=m 时,求函数()()()F x f x g x =-在],0(a 的最大值;(3)证明:当3m ≥-时,不等式2()()(2)e x f x g x x x +<--对任意1[,1]2x ∈均成立(其中e 为自然对数的底数,e 2.718...=).20.(本题满分16分)已知数列{}n a 各项均为正数,11a =,22a =,且312n n n n a a a a +++=对任意*n ∈N 恒成立,记{}n a 的前n 项和为n S . (1)若33a =,求5a 的值;(2)证明:对任意正实数p ,221{}n n a pa -+成等比数列;(3)是否存在正实数t ,使得数列{}n S t +为等比数列.若存在,求出此时n a 和n S 的表达式;若不存在,说明理由.2017—2018学年第一学期高三期中调研试卷数学 (附加) 2017.11 注意事项:1.本试卷共2页.满分40分,考试时间30分钟.2.请在答题卡上的指定位置作答,在本试卷上作答无效.3.答题前,请务必将自己的姓名、学校、考试证号填写在答题卡的规定位置.21.【选做题】本题包括A、B、C、D四小题,请选定其中两题,并在相应的答题区域内作答....................若多做,则按作答的前两题评分.解答时应写出文字说明、证明过程或演算步骤.A.(几何证明选讲)(本小题满分10分)如图,AB为圆O的直径,C在圆O上,CF AB⊥于F,点D为线段CF上任意一点,延长AD交圆O于E,030AEC∠=.(1)求证:AF FO=;(2)若CF=AD AE⋅的值.B.(矩阵与变换)(本小题满分10分)已知矩阵1221⎡⎤=⎢⎥⎣⎦A,42α⎡⎤=⎢⎥⎣⎦u r,求49αu rA的值.C.(极坐标与参数方程) (本小题满分10分)在平面直角坐标系中,直线l的参数方程为42525x ty t⎧=-+⎪⎪⎨⎪=⎪⎩(t为参数),以原点O为极点,x轴正半轴为极轴建立极坐标系,圆C的极坐标方程为cos()(0)4aρθπ=-≠.(1)求直线l和圆C的直角坐标方程;(2)若圆C任意一条直径的两个端点到直线la的值.BD .(不等式选讲) (本小题满分10分)设,x y 均为正数,且x y >,求证:2212232x y x xy y ++-+≥.【必做题】第22、23题,每小题10分,共计20分.请在答题卡指定区域.......内作答,解答时应写出文字说明、证明过程或演算步骤. 22.(本小题满分10分)在小明的婚礼上,为了活跃气氛,主持人邀请10位客人做一个游戏.第一轮游戏中,主持人将标有数字1,2,…,10的十张相同的卡片放入一个不透明箱子中,让客人依次去摸,摸到数字6,7,…,10的客人留下,其余的淘汰,第二轮放入1,2,…,5五张卡片,让留下的客人依次去摸,摸到数字3,4,5的客人留下,第三轮放入1,2,3三张卡片,让留下的客人依次去摸,摸到数字2,3的客人留下,同样第四轮淘汰一位,最后留下的客人获得小明准备的礼物.已知客人甲参加了该游戏. (1)求甲拿到礼物的概率;(2)设ξ表示甲参加游戏的轮数..,求ξ的概率分布和数学期望()E ξ.23.(本小题满分10分)(1)若不等式(1)ln(1)x x ax ++≥对任意[0,)x ∈+∞恒成立,求实数a 的取值范围; (2)设*n ∈N ,试比较111231n ++++L 与ln(1)n +的大小,并证明你的结论.2017—2018学年第一学期高三期中调研试卷数 学 参 考 答 案一、填空题(本大题共14小题,每小题5分,共70分)1.{1} 2.(1,2)(2,)+∞U 3.充分不必要 4.1 5.136.4 7.3π 8.(2,0)(1,2)-U 9.45- 10.(1,2]11.12018121 13.2π 14.1(1,e )e +二、解答题(本大题共6个小题,共90分) 15.(本题满分14分)解:(1)∵()f x 图象上相邻两个最高点之间的距离为2π, ∴()f x 的周期为2π,∴202||2a a ππ=>且,······································································2分∴2a =,··················································································································4分此时1())42f x x b π=+++, 又∵()f x 的图象与x 轴相切,∴1||02b b +=>,·······················································6分 ∴12b =-;··········································································································8分(2)由(1)可得())242f x x π=++, ∵[0,]4x π∈,∴4[,]444x ππ5π+∈,∴当444x π5π+=,即4x π=时,()f x 有最大值为;·················································11分当442x ππ+=,即16x π=时,()f x 有最小值为0.························································14分 16.(本题满分14分) 解:由题意得b c +=,240a bc -=.···············································································2分(1)当52,4a m ==时,5,12b c bc +==, 解得212b c =⎧⎪⎨=⎪⎩或122b c ⎧=⎪⎨⎪=⎩;································································································6分(2)2222222222()()22cos 23222a ma abc a b c bc a A m a bc bc--+-+--====-,····························8分∵A 为锐角,∴2cos 23(0,1)A m =-∈,∴2322m <<,····················································11分又由b c ma +=可得0m >,·························································································13分∴m <····································································14分 17.(本题满分15分)解:(1)∵*131()n n S S n +=+∈N ,∴*131(,2)n n S S n n -=+∈N ≥,∴*13(,2)n n a a n n +=∈N ≥,·························································································2分又当1n =时,由2131S S =+得23a =符合213a a =,∴*13()n n a a n +=∈N ,······························3分∴数列{}n a 是以1为首项,3为公比的等比数列,通项公式为1*3()n n a n -=∈N ;·····················5分(2)∵*113()n n n na b b n a ++-==∈N ,∴{}n b 是以3为首项,3为公差的等差数列,····················7分∴*33(1)3()n b n n n =+-=∈N ,·····················································································9分∴2n n a b n λ+≤,即1233n n n λ-⋅+≤,即2133n n nλ--≤对*n ∈N 有解,··································10分设2*13()()3n n n f n n --=∈N ,∵2221(1)3(1)32(41)(1)()333n n nn n n n n n f n f n -+-+---++-=-=, ∴当4n ≥时,(1)()f n f n +<,当4n <时,(1)()f n f n +>,∴(1)(2)(3)(4)(5)(6)f f f f f f <<<>>>L , ∴max 4[()](4)27f n f ==,···························································································14分∴427λ≤.·············································································································15分 18.(本题满分15分)解:(1)当01x <≤时,过A 作AK CD ⊥于K (如上图),则1AK =,122CD AB DK -==,1HM x =-, 由2AK MH DK DH ==,得122HM x DH -==, ∴322HG DH x =-=+, ∴2()(1)(2)2S x HM HG x x x x =⋅=-+=--+;·······························································4分当512x <<时,过E 作ET MN ⊥于T ,连结EN (如下图),则1ET x =-,2MN TN ==∴MN = ∴()(1)S x MN ET x =⋅=-,······································································8分综上:22,01()52(12x x x S x x x ⎧--+<⎪=⎨-<<⎪⎩≤;·································································9分(2)当01x <≤时,2219()2()24S x x x x =--+=-++在[0,1)上递减, ∴max ()(0)2S x S ==;································································································11分2︒当512x <<时,229(1)(1)94()2(224x x S x x -+--=-⋅=,当且仅当(1)x -51(1,)2x =+∈时取“=”, ∴max 9()4S x =,此时max 9()24S x =>,∴()S x 的最大值为94,············································14分答:当MN 与AB 之间的距离为1米时,通风窗的通风面积S 取得最大值.····················15分19.(本题满分16分)解:(1)设切点坐标为00(,ln )x x ,则切线方程为0001ln ()y x x x x -=-, 将(0,1)P -代入上式,得0ln 0x =,01x =, ∴切线方程为1y x =-;·······························································································2分(2)当0m =时,2()ln ,(0,)F x x x x x =-+∈+∞, ∴(21)(1)(),(0,)x x F x x x+-'=-∈+∞,············································································3分当01x <<时,()0F x '>,当1x >时,()0F x '<, ∴()F x 在(0,1)递增,在(1,)+∞递减,·············································································5分∴当01a <≤时,()F x 的最大值为2()ln F a a a a =-+; 当1a >时,()F x 的最大值为(1)0F =;········································································7分(3)2()()(2)e x f x g x x x +<--可化为(2)e ln x m x x x >-+-,设1()(2)e ln ,[,1]2x h x x x x x =-+-∈,要证3m ≥-时()m h x >对任意1[,1]2x ∈均成立, 只要证max ()3h x <-,下证此结论成立. ∵1()(1)(e )x h x x x '=--,∴当112x <<时,10x -<,·······················································8分设1()e x u x x =-,则21()e 0x u x x '=+>,∴()u x 在1(,1)2递增, 又∵()u x 在区间1[,1]2上的图象是一条不间断的曲线,且1()202u =<,(1)e 10u =->,∴01(,1)2x ∃∈使得0()0u x =,即001e x x =,00ln x x =-,····················································11分当01(,)2x x ∈时,()0u x <,()0h x '>;当0(,1)x x ∈时,()0u x >,()0h x '<; ∴函数()h x 在01[,]2x 递增,在0[,1]x 递减, ∴0max 00000000012()()(2)e ln (2)212x h x h x x x x x x x x x ==-+-=-⋅-=--,····························14分∵212y x x =--在1(,1)2x ∈递增,∴0002()121223h x x x =--<--=-,即m a x ()3h x <-, ∴当3m ≥-时,不等式2()()(2)e x f x g x x x +<--对任意1[,1]2x ∈均成立.··························16分 20.(本题满分16分) 解:(1)∵1423a a a a =,∴46a =,又∵2534a a a a =,∴54392a a ==;·······································2分(2)由3121423n n n n n n n n a a a a a a a a +++++++=⎧⎨=⎩,两式相乘得2134123n n n n n n n a a a a a a a ++++++=,∵0n a >,∴2*42()n n n a a a n ++=∈N , 从而{}n a 的奇数项和偶数项均构成等比数列,···································································4分设公比分别为12,q q ,则1122222n n n a a q q --==,1121111n n n a a q q ---==,······································5分又∵312=n n n na a a a +++,∴42231122a a q a a q ===,即12q q =,···························································6分设12q q q ==,则2212223()n n n n a pa q a pa ---+=+,且2210n n a pa -+>恒成立, 数列221{}n n a pa-+是首项为2p +,公比为q 的等比数列,问题得证;····································8分(3)法一:在(2)中令1p =,则数列221{}n n a a -+是首项为3,公比为q 的等比数列,∴22212223213 ,1()()()3(1),11k k k k k k k q S a a a a a a q q q---=⎧⎪=++++++=-⎨≠⎪-⎩, 12122132 ,13(1)2,11k k k k k k k q q S S a q q q q ---⎧-=⎪=-=⎨--≠⎪-⎩,·····································································10分且12341,3,3,33S S S q S q ===+=+,∵数列{}n S t +为等比数列,∴22132324()()(),()()(),S t S t S t S t S t S t ⎧+=++⎪⎨+=++⎪⎩ 即22(3)(1)(3),(3)(3)(33),t t q t q t t q t ⎧+=+++⎪⎨++=+++⎪⎩,即26(1),3,t q t t q +=+⎧⎨=-⎩ 解得14t q =⎧⎨=⎩(3t =-舍去),·························································································13分∴224121k k k S =-=-,212121k k S --=-, 从而对任意*n ∈N 有21n n S =-, 此时2n n S t +=,12n n S tS t-+=+为常数,满足{}n S t +成等比数列,当2n ≥时,111222n n n n n n a S S ---=-=-=,又11a =,∴1*2()n n a n -=∈N ,综上,存在1t =使数列{}n S t +为等比数列,此时1*2,21()n n n n a S n -==-∈N .······················16分法二:由(2)知,则122n n a q -=,121n n a q --=,且12341,3,3,33S S S q S q ===+=+,∵数列{}n S t +为等比数列,∴22132324()()(),()()(),S t S t S t S t S t S t ⎧+=++⎪⎨+=++⎪⎩ 即22(3)(1)(3),(3)(3)(33),t t q t q t t q t ⎧+=+++⎪⎨++=+++⎪⎩,即26(1),3,t q t t q +=+⎧⎨=-⎩ 解得14t q =⎧⎨=⎩(3t =-舍去),·······················································································11分∴121222n n n a q --==,22212n n a --=,从而对任意*n ∈N 有12n n a -=,····································13分∴01211222222112n n n n S --=++++==--, 此时2n n S t +=,12n n S tS t-+=+为常数,满足{}n S t +成等比数列,综上,存在1t =使数列{}n S t +为等比数列,此时1*2,21()n n n n a S n -==-∈N .······················16分21.【选做题】本题包括A 、B 、C 、D 四小题,请选定其中两题,并在相应的答题区域内作答....................若多做,则按作答的前两题评分.解答时应写出文字说明、证明过程或演算步骤. A .(几何证明选讲,本小题满分10分)解:(1)证明 :连接,OC AC ,∵030AEC ∠=,∴0260AOC AEC ∠=∠=,又OA OC =,∴AOC ∆为等边三角形,∵CF AB ⊥,∴CF 为AOC ∆中AO 边上的中线, ∴AF FO =;······································································5分(2)解:连接BE ,∵CF =AOC ∆是等边三角形, ∴可求得1AF =,4AB =,B∵AB 为圆O 的直径,∴90AEB ∠=o ,∴AEB AFD ∠=∠, 又∵BAE DFA ∠=∠,∴AEB ∆∽AFD ∆,∴AD AFAB AE=, 即414AD AE AB AF ⋅=⋅=⨯=.··················································································10分 B .(矩阵与变换,本小题满分10分) 解:矩阵A 的特征多项式为212()2321f λλλλλ--==----, 令()0f λ=,解得矩阵A 的特征值121,3λλ=-=,····························································2分当11λ=-时特征向量为111α⎡⎤=⎢⎥-⎣⎦u u r,当23λ=时特征向量为211α⎡⎤=⎢⎥⎣⎦u u r,·····································6分又∵12432ααα⎡⎤==+⎢⎥⎣⎦u ru u r u u r,······························································································8分∴5049494911225031331αλαλα⎡⎤-=+=⎢⎥+⎣⎦u r u u r u u rA .···········································································10分C .(极坐标与参数方程,本小题满分10分) 解:(1)直线l 的普通方程为220x y +-=;··········································································3分。

高2021届高2018级江苏省苏州市高三第一学期期中考试数学试题参考答案

高2021届高2018级江苏省苏州市高三第一学期期中考试数学试题参考答案

高2021届高2018级高三年级第一学期期中考试(苏州)数学参考答案及评分标准1. C2. C3. B4. B5. A6. B7. C8. A9. BC 10. BC 11. ABD 12. ABC13. (-2,2)∪(2,+∞) 14. 1215. 40 000 16. 2 17. 解:(1) 因为函数f(x)的最小正周期为π,所以2πω=π,ω=2,(1分) 此时g(φ)=f(π6)=sin(π3-φ)=-sin (φ-π3). 因为|φ|≤π2,所以φ-π3∈[-5π6,π6],所以-1≤sin(φ-π3)≤12,(3分) 所以g(φ)=f(π6)的值域为[-12,1].(4分) (2) 因为φ=π3,所以f(α)=sin (2α-π3). 由sin α-2cos α=0,得tan α=2,(6分)f (α)=sin (2α-π3)=12sin 2α-32cos 2α(8分) =12×2 tan α1+tan 2α-32×1-tan 2α1+tan 2α=4-3×(1-4)2×(1+4)=4+3310.(10分) 18. 解:(1) 当a =3时,f(x)=-13x 3+32x 2-2x,得f′(x)=-x 2+3x -2.(1分) 因为f′(x)<0,得x <1或x >2,(3分)所以函数f(x)单调递减区间为(-∞,1)和(2,+∞).(4分)(2) 由f(x)=-13x 3+a 2x 2-2x,得f′(x)=-x 2+ax -2.(5分) 因为对于任意x ∈[1,+∞)都有f′(x)<2(a -1)成立,所以问题转化为:对于任意x ∈[1,+∞)都有f′(x)max <2(a -1).(6分)因为f′(x)=-(x -a 2)2+a 24-2,其图象开口向下,对称轴为x =a 2. ①当a 2<1时,即a <2时,f ′(x)在[1,+∞)上单调递减, 所以f′(x)max =f′(1)=a -3.由a -3<2(a -1),得a >-1,此时-1<a <2.(8分)②当a 2≥1,即a ≥2时,f ′(x)在[1,a 2]上单调递增,在(a 2,+∞)上单调递减, 所以f′(x)max =f′(a 2)=a 24-2.(10分) 由a 24-2<2(a -1),得0<a <8,此时2≤a <8.(11分) 综合①②,可得实数a 的取值范围是(-1,8).(12分)19. 解:若选①.(1) 由题设条件及正弦定理,得sin Csin B +C 2=sin Asin C.(1分)因为△ABC 中,sin C ≠0,所以sin B +C 2=sin A.(2分) 由A +B +C =π,可得sin B +C 2=sin π-A 2=cos A 2,(3分) 所以cos A 2=2sin A 2cos A 2.(4分) 因为△ABC 中,cos A 2≠0,所以sin A 2=12. 因为0<A <π,所以A =π3.(5分) 因为c =(3-1)b,所以由正弦定理得sin C =(3-1)sin B.因为A =π3,所以sin B =sin(π-A -C)=sin(A +C)=sin(C +π3),(6分) 所以sin C =(3-1)sin(C +π3),整理得sin C =cos C.(7分) 因为△ABC 中,sin C ≠0,所以cos C ≠0,所以tan C =sin C cos C=1. 因为0<C <π,所以C =π4.(9分) (2) 因为△ABC 的面积为3-3,c =(3-1)b,A =π3, 所以由S =12bcsin A 得34(3-1)b 2=3-3,(11分) 解得b =2.(12分)若选②.(1) 由题设及正弦定理得2cos A(sin Bcos C +sin Ccos B)=sin A,(1分) 即2cos Asin(B +C)=sin A.(2分)因为B +C =π-A,所以2cos Asin A =sin A.(3分)因为△ABC 中,sin A ≠0,所以cos A =12.(4分) 因为0<A <π,所以A =π3.(5分) 下同选①.若选③.由题设得(sin B -sin C)2=sin 2A -sin Bsin C,(1分)所以sin 2B +sin 2C -sin 2A =sin Bsin C.(2分)由正弦定理得b 2+c 2-a 2=bc.由余弦定理得cos A =b 2+c 2-a 22bc =12.(4分) 因为0<A <π,所以A =π3.(5分) 下同选①.20. 解:(1) 因为等差数列{a n }中,a 3+a 5+a 7=3a 5=30,所以a 5=10.设等差数列{a n }的公差是d,所以d =a 5-a 15-1=2,(1分) 所以a n =a 1+(n -1)d =2n.(2分)设等比数列{b n }的公比是q,因为b 2b 3=a 16,所以b 21q 3=4q 3=32,所以q =2,所以b n =b 1qn -1=2n .(3分) (2) ① 若存在正整数k,使得T k +1=T k +b k +32成立,则b k +1=b k +32,(4分)所以2k +1=2k +32,即2k =32,解得k =5.(5分)存在正整数k =5满足条件.(6分)② S n =n (a 1+a n )2=n(n +1), 所以n(n +1)≥2n ,即2n -n(n +1)≤0.(8分)令f(n)=2n -n(n +1),因为f(n +1)-f(n)=2n +1-(n +1)(n +2)-2n +n(n +1)=2[2n -1-(n +1)],所以当n ≥4时,{f(n)}单调递增.(9分)又f(2)-f(1)<0,f(3)-f(2)<0,f(4)-f(3)<0,所以f(1)>f(2)>f(3)=f(4)<…<f(n)<…(10分)因为f(1)=0,f(4)=-4,f(5)=2,所以n =1,2,3,4时,f(n)≤0,n ≥5时,f(n)>0,(11分)所以不等式S n ≥b n 的解集为{1,2,3,4}.(12分)21. 解:(1) 因为g(x)为定义在[-4,4]上的奇函数,所以当x ∈[-4,0)时,g(-x)=-(-x)2+4(-x)=-x 2-4x.因为g(-x)=-g(x),所以g(-x)=-g(x)=-x 2-4x,(2分)所以g(x)=x 2+4x,所以g(x)=⎩⎪⎨⎪⎧x 2+4x ,x ∈[-4,0),-x 2+4x ,x ∈[0,4].(3分) (2) 因为g(x)在[2,4]内有“8倍倒域区间”,设2≤a <b ≤4,因为g(x)在[2,4]上单调递减,所以⎩⎨⎧-a 2+4a =8a ,-b 2+4b =8b ,整理得⎩⎪⎨⎪⎧(a -2)(a 2-2a -4)=0,(b -2)(b 2-2b -4)=0,(5分) 解得a =2,b =1+5,所以g(x)在[2,4]内的“8倍倒域区间”为[2,1+5].(6分)(3) 因为g(x)在x ∈[a,b]时,函数值的取值区间恰为[k b ,k a](k ≥8), 所以0<a <b ≤4或-4≤a <b <0.当0<a <b ≤4时,因为g(x)的最大值为4,所以k a≤4.(7分) 因为k ≥8,所以a ≥2.因为g(x)在[2,4]上单调递减,所以⎩⎨⎧-a 2+4a =k a,-b 2+4b =k b ,即⎩⎪⎨⎪⎧a 3-4a 2+k =0,b 3-4b 2+k =0,(8分) 所以方程x 3-4x 2+k =0在[2,4]上有两个不同的实数解.令h(x)=x 3-4x 2+k,x ∈[2,4],则h′(x)=3x 2-8x.令h′(x)=3x 2-8x =0,得x =0(舍去)或x =83, 当x ∈(2,83)时,h ′(x)<0,所以h(x)在(2,83)上单调递减. 当x ∈(83,4)时,h ′(x)>0,所以h(x)在(83,4)上单调递增.(10分) 因为h(2)=k -8≥0,h(4)=k ≥8,所以要使得x 3-4x 2+k =0在[2,4]上有两个不同的实数解,只需h(83)<0, 解得k <25627,所以8≤k <25627.(11分) 同理可得:当-4≤a <b <0时,8≤k <25627. 综上所述,k 的取值范围是[8,25627).(12分) 22. (1) 解:因为f(x)=e x +ax·sin x,所以f′(x)=e x +a(sin x +xcos x),(1分) 所以f′(0)=1.因为f(0)=1,所以曲线f(x)在x =0处的切线方程为y -1=x,即y =x +1.(3分)(2) 证明:当a =-2时,g(x)=e x x-2sin x,其中x ∈(-π,0), 则g′(x)=e x (x -1)x 2-2cos x =e x (x -1)-2x 2cos x x 2.(4分) 令h(x)=e x (x -1)-2x 2cos x,x ∈(-π,0),则h′(x)=x(e x +2xsin x -4cos x).当x ∈(-π,-π2)时,因为e x >0,2xsin x >0,cos x <0,所以h′(x)<0, 所以h(x)在(-π,-π2)上单调递减.(5分) 因为h(-π)=2π2-e -π(1+π)>0,h(-π2)=e -π2(-π2-1)<0, 所以由零点存在性定理知,存在唯一的x 0∈(-π,-π2),使得h(x 0)=0,(7分) 所以当x ∈(-π,x 0)时,h(x)>0,即g′(x)>0;当x ∈(x 0,-π2)时,h(x)<0,即g ′(x)<0. 当x ∈(-π2,0)时,g ′(x)=e x (x -1)x 2-2cos x <0. 因为g′(x)在(-π,0)上连续,所以x ∈(x 0,0)时,g ′(x)<0,所以g(x)在(-π,x 0)上单调递增,在(x 0,0)上单调递减,所以x 0是函数g(x)在(-π,0)上的唯一极大值点.(9分)因为g(x)在(x 0,-π2)上单调递减,所以g(x 0)>g(-π2). 因为g(-π2)=-1π2e π2+2>0,所以g(x 0)>0.(10分)当x 0∈(-π,-π2)时,因为-1<ex 0x 0<0,0<-2sin x 0<2, 所以g(x 0)=ex 0x 0-2sin x 0<2,(11分) 所以0<g(x 0)<2.(12分)。

(精品word)2018-2019学年苏州第一学期高三数学期中调研测试(正题及详细答案)

(精品word)2018-2019学年苏州第一学期高三数学期中调研测试(正题及详细答案)

2018—2019学年第一学期高三期中调研试卷 数学(正题) 2018.11注意事项:1.本试卷共4页.满分160分,考试时间120分钟.2.请将填空题的答案和解答题的解题过程写在答题卷上,在本试卷上答题无效. 3.答题前,务必将自己的姓名、学校、准考证号写在答题纸的密封线内.一、填空题(本大题共14小题,每小题5分,共70分,请把答案直接填写在答卷纸...相应的位置)1.设全集{}=1,2,3,4,5U ,若集合{}3,4,5A =,则U A =ð ▲ . 2.命题“2,210x R x x ≥∃∈-+”的否定是 ▲ .3.已知向量(2,)m =a ,(1,2)=-b ,且⊥a b ,则实数m 的值是 ▲ . 4.函数()lg(2)2f x x x =-++的定义域是 ▲ .5.已知扇形的半径为6,圆心角为3π,则扇形的面积为 ▲ . 6.已知等比数列{}n a 的前n 项和为n S ,424SS =,则84S S = ▲ .7.设函数()sin()f x A x ωϕ=+(,,A ωϕ为常数, 且0,0,0A ωϕ>><<π)的部分图象如图所示, 则ϕ的值为 ▲ .8.已知二次函数2()23f x x x =-++,不等式()f x m ≥的解集的区间长度为6(规定:闭区间[],a b 的长度为b a -),则实数m 的值是 ▲ .9.某工厂建造一个无盖的长方体贮水池,其容积为48003m ,深度为3m .如果池底每12m 的造价为150元,池壁每12m 的造价为120元,要使水池总造价最低,那么水池底部的周长为 ▲ m .10.在ABC △中,sin 2sin cos 0A B C +=,则A 的最大值是 ▲ .11.已知函数()2,1,eln ,1,x x f x x x x≥+<=⎧⎪⎪⎨⎪⎪⎩,若()()()()123123f x f x f x x x x ==<<,则()13x f x 的取值范围是 ▲ .12.已知数列{}n a 的通项公式为51n a n =+,数列{}n b 的通项公式为2n b n =,若将数列{}n a ,{}n b 中相同的项按从小到大的顺序排列后看作数列{}n c ,则6c 的值为 ▲ .13.如图,在平面四边形ABCD 中,AB BC ⊥,AD CD ⊥,60BCD ∠=︒,CB CD ==若点M 为边BC 上的动点,则AM DM uuu r uuu u r⋅的最小值为 ▲ .14.函数()xf x e x a =-在(1,2)-上单调递增,则实数a 的取值范围是 ▲ .二、解答题(本大题共6个小题,共90分,请在答题卷区域内作答,解答时应写出文字说明、证明过程或演算步骤) 15.(本题满分14分)已知(2cos23,2sin2)αα=+m ,(sin ,cos )ββ=n . (1)若6βπ=,且()f α=⋅m n ,求()f α在[0,]2π上的取值范围; (2)若//m n ,且αβ+、α的终边不在y 轴上,求tan()tan αβα+的值.16.(本题满分14分)已知等差数列{}n a 的前n 项和为n A , 35a =,636A =.数列{}n b 的前n 项和为n B ,且21n n B b =-.(1)求数列}{n a 和{}n b 的通项公式;(2)设n n n c a b =⋅,求数列{}n c 的前n 项和n S .CBADM17 .(本题满分14分)某湿地公园围了一个半圆形荷花塘如图所示,为了提升荷花池的观赏性,现计划在池塘的中轴线OC 上设计一个观景台D (点D 与点O ,C 不重合),其中AD ,BD ,CD 段建设架空木栈道,已知2AB =km ,设建设的架空木栈道的总长为y km .(1)设(rad)DAO θ∠=,将y 表示成θ的函数关系式,并写出θ的取值范围; (2)试确定观景台的位置,使三段木栈道的总长度最短.18.(本题满分16分)已知()x xaf x e e =-是奇函数. (1)求实数a 的值;(2)求函数222()x x y e e f x λ-=+-在),0[∞+∈x 上的值域; (3)令()()2g x f x x =-,求不等式32(1)(13)0g x g x ++-<的解集.CBA荷花DO荷花 荷花荷花19.(本题满分16分)已知数列{}n a 的首项为1,定义:若对任意的*n N ∈,数列{}n a 满足13n n a a +->,则称数列{}n a 为“M 数列”.(1)已知等差数列{}n a 为“M 数列”, 其前n 项和S n 满足2S 22n n n <+()*n N ∈,求数列{}n a 的公差d 的取值范围;(2)已知公比为正整数的等比数列{}n a 为“M 数列”,记数列{}n b 满足34n n b a =,且数列{}n b 不为“M 数列,求数列{}n a 的通项公式.20.(本题满分16分)设函数()1ln f x ax x =--,a 为常数.(1)当2a =时,求()f x 在点(1,(1))f 处的切线方程; (2)若12,x x 为函数()f x 的两个零点,12x x >. ①求实数a 的取值范围; ②比较12x x +与2a的大小关系,并说明理由.2018—2019学年第一学期高三期中调研试 数学参考答案与评分标准 2018.11 一、填空题(本大题共14小题,每小题5分,共70分)1. {}1,22. 2,210x R x x ∀∈-+<3. 14. [)2,2-5. 6π6. 107.3π8. 5- 9. 160 10. π6 11. 2(1,0)e - 12. 256 13. 21414. -1a ≤或3a ≥二、解答题(本大题共6个小题,共90分,请在答题卷区域内作答,解答时应写出文字说明、证明过程或演算步骤) 15.(本题满分14分) 解:(1)因为6βπ=,所以1(2=n .所以3()cos222f ααα=⋅++m n =, ………………2分 即3()2sin(2)62f παα=++, ………………3分 因为[0,]2απ∈,所以72[,]666απππ+∈;所以1sin(2)[,1]62απ+∈-; ………………5分所以()f α的取值范围是17[,]22. ………………7分(2)由//m n ,所以(2cos23)cos 2sin2sin 0αβαβ+-=, ………………9分 所以2cos(2)3cos 0αββ++=, ………………10分 所以2cos()cos 2sin()sin 3cos()cos 3sin()sin 0αβααβααβααβα+-+++++=, 因为αβ+、α的终边不在y 轴上,所以cos(),cos αβα+均不为0,所以5cos()cos sin()sin 0αβααβα+++=, ………………12分 因为所以tan()tan 5αβα+=-. ………………14分 16.(本题满分14分)解:(1)因为{}n a 是等差数列,设{}n a 的公差为d ,由35a =,636A =,得1125,2512,a d a d +=⎧⎨+=⎩ ………………2分所以11a =,2d =,所以21n a n =-; ………………4分 由21n n B b =-可知,当1n =时,11b =; ………………5分 当2n ≥时,1121n n B b --=-,所以1122n n n n B B b b ---=-,从而12(2)n n b b n -=≥, ………………7分 又11b =,所以12(2)nn b n b -=≥,所以{}n b 是等比数列, ………………8分 所以12n n b -=. ………………9分(2)因为n n n c a b =⋅,所以1(21)2n n c n -=-⋅,01221123123252(23)2(21)2n n n n S c c c c n n --=++++=⋅+⋅+⋅++-+-L L ,12312123252(23)2(21)2n n n S n n -=⋅+⋅+⋅++-+-L , ………………11分所以01212212222222(21)212(21)212nn nn n S n n ---=⋅+⋅+⋅++⋅--=+⨯---L ,所以(23)23n n S n =-+. ………………14分 17. (本题满分14分) 解:(1)由DAO θ∠=,OC AB ⊥,1OA OB ==,则1cos DA DB θ==,tan DO θ=,所以1tan DC θ=-, ………………4分 所以22sin 1tan 1cos cos y DA DB DC θθθθ-=++=+-=+,04πθ<<. ………………7分(注:表达式2分,θ的的取值范围1分)(2) 22sin 1cos y θθ-'=, ………………9分令0y '=,得1sin 2θ=,又04πθ<<,所以6πθ=, ………………10分当06πθ<<时,0y '<,y 是θ的减函数;当64ππθ<<时,0y '>,y 是θ的增函数.………………12分所以,当6πθ=时,min 1y =+,此时tan DO θ==………………13分 答:当D 位于线段AB 的中垂线上且距离AB处时,能使三段木栈道总长度最短. ………………14分18.(本题满分16分) 解:(1)函数的定义域为R ,因为()f x 为奇函数,由()()f x f x -=-可知,(0)0f =,所以10a -=,所以1a =; ………………3分 当1a =时,11()()x xx x f x e e f x e e---=-=-+=-,此时()f x 为奇函数. ………………4分(2)令1x x e t e -=(0t ≥),所以22212xxe t e+=+ 所以2()22h t t t λ=-+,对称轴t λ=, ………………5分 ①当0λ≤时,[)()(0),h t h ∈+∞,所求值域为[)2,+∞; ………………7分②当0λ>时,[)()(),h t h λ∈+∞,所求值域为)22,λ⎡-+∞⎣; ………………9分(3)因为1()x xf x e e =-为奇函数,所以()()2()()2(),g x f x x f x x g x -=---=-+=- 所以()()2g x f x x =-为奇函数,所以32(1)(13)0g x g x ++-<等价于32(1)(31)g x g x +<-, ………………10分 又1()()22220x x g x f x e e''=-=+--=≥当且仅当0x =时,等号成立, 所以()()2g x f x x =-在R 上单调增,所以32131x x +<-, ………………13分 即32320x x -+<,又32232(1)(22)0x x x x x -+=---<,所以1x <-11x <<+ ………………15分所以不等式的解集是(,1(1,1-∞-+U . ………………16分 19.(本题满分16分)解:(1)因为等差数列{}n a 为“M 数列”,所以3d >, ………………2分由 11a =,得 (1)2n n n S n d -=+, 由题意,得2(1)222n n n d n n -+<+对n N *∈均成立,即()142n d n -<+对n N *∈均成立, …………………4分 当1n =时,3d >均成立; …………………5分当2n ≥时,421n d n +<-恒成立,因为4264411n n n +=+>--,所以34d <≤, ………………7分综上可得,数列{}n a 的公差d 的取值范围是34d <≤. …………………8分 (2)设数列{}n a 的公比为q ,则111n n n a a q q --==, 因为公比为正整数的等比数列{}n a 为“M 数列”, 所以1111(1)(1)3n n n n a a a q q q q --+-=-=->,所以q 至少为大于等于2的正整数; …………………9分 又112n nn n a a q a a +--=-≥,所以数列1{}n n a a --单调递增,所以在数列1{}n n a a --中,21a a -为最小项, …………………11分 由{}n a 为“M 数列”,可知只需213a a ->,即 13q ->,所以4q > ………12分 同理,在1{}n n b b --中,“21b b -”为最小项, 因为{}n b 不是“M 数列”,所以存在13m m b b --≤,又“21b b -”为最小项,所以213b b -≤, 即 1(1)4a q -≤,所以5q ≤…………………14分 因为*q N ∈,5q 所以=,15n n a -=. …………………16分 20.(本题满分16分)解:(1)当2a =时,()21ln f x x x =--,得1()2f x x'=-, 所以(1)1f '=,所以()f x 在点(1,(1))f 处的切线方程为y x =; ………………3分 (2)①()1ln f x ax x =--(0x >),得11()ax f x a x x-'=-=, 当0a ≤时,()0f x '<,()f x 单调递减不满足题意; ………………4分当0a >时,1(0,)x a ∈,()0f x '<;1(,)x a ∈+∞,()0f x '>;所以()f x 在1(0,)a 上单调减,在1(,)a+∞上单调增.因为函数()f x 有两个零点,所以min 1()()0f x f a=<,得01a <<. …………6分下证:在区间1(0,)a 和1(,)a+∞内分别存在一个零点.在1(0,)a 内,因为1()0a f e e =>,而1()0f a<,又()f x 在1(0,)a 上单调减,所以由零点存在性原理可知:在1(0,)a内()f x 有一个零点; ………………9分法一:在1(,)a+∞内,可以证明ln 1x x x ≤-<,所以ln x <,所以211()1ln 1)1f x ax x ax a a a=-->--=--,取202(1)x a =+,得221111)1(1)110a a a a a a a ---=+--=+>, 而1()0f a <,又()f x 在1(,)a +∞上单调递增,所以由零点存在性原理可知:在1(,)a+∞内()f x 有一个零点. ………………12分 法二:在1(,)a +∞内,因为ln 1x x x ≤-<(易证),所以即ln x <,所以()1ln 1f x ax x ax =-->--t =且2()21g t at t =--,因为01a <<,所以存在0t ,使得0()0g t >,所以0()0f t >,而1()0f a<,又()f x 在1(,)a +∞上单调增,所以由零点存在性原理可知在1(,)a+∞内,()f x 有一个零点. ………………12分法三:在1(,)a+∞内取20a x e =,所以2202224()1(2)2a aa f x ae e a a a =--=--,令2(2)t t a=>,2()2t g t e t t =--,可证:2t e t >, 所以22()2(1)0t g t e t t t t t t =-->-=->,所以0()0f x >,而1()0f a<,又()f x 在1(,)a +∞上单调增,所以由零点存在性原理可知在1(,)a+∞内,()f x 有一个零点. ………………12分②122x x a+>. ………………13分 证明如下:由111ln 0ax x --=,221ln 0ax x --=,所以1122()ln xa x x x -=即1212lnx x a x x =-,要证122x x a +>,即证1122122()ln x x x x x x ->+,即证1121222(1)ln 1x x x x x x ->+,令12(1)x t t x =>,令2(1)()ln 1t h t t t -=-+,()()22214(1)()011t h t t t t t -'=-=>++,所以()(1)0h t h >=,所以122x x a+>. ………………16分。

江苏省苏州中学2017-2018学年度第一学期期中考试数学试题(3页)

江苏省苏州中学2017-2018学年度第一学期期中考试数学试题(3页)

江苏省苏州中学2017-2018学年度第一学期期中考试数学试题高三数学(正题部分)一.填空题:本大题共有14道小题,每小题5分,计70分,请把答案填写在相应的位置上1.已知集合{}=2,0,1A -,{}1,0B =-,则A B =U _____________.2.已知α是锐角,若tan 3α=,则cos α=_____________.3.△ABC 中,已知1a =,60A =o,3c =,则角C =_________. 4.若函数()32x x a f x e x x e =-+-是奇函数,则实数a 的值为_____________ 5.函数ln ()(0)x f x x x=>的单调递增区间是_ 6.函数()f x =的定义域为_____________.7.若曲线x y e =切线方程为y x b =+,则实数b =_____________.8.若“12x <<”是“230x ax -+<”的充分非必要条件,则实数a 的取值范围为______. 9.已知cos 6πα⎛⎫-= ⎪⎝⎭,则sin 26πα⎛⎫+= ⎪⎝⎭_____________. 10.已知0,2x π⎛⎫∈ ⎪⎝⎭,函数2cos y x =与3tan y x =图象相交于点P ,过点P 作PQ 垂直x 轴,垂足为点Q ,线段PQ 与函数sin y x =的图象交于点M ,则线段MQ 的长度为_____________.11.已知函数()f x 定义域为D ,若存在0x D ∈,使()()()0011f x f x f +=+成立,则称()f x 具有性质P .现给出下列四个函数:① ()1f x x= ; ②()2x f x =; ③()()2log 2f x x =+; ④()sin f x x π= 其中具有性质P 的函数为_____________(注:填上你认为正确的所有函数序号)12.若实数x 、y 满足22sin 1x y +=,则sin x y -的取值范围为_____________. 13.已知m 、n *∈N ,若1tan m α=,1tan n β=,且4παβ+=,则m n +的值为________. 14.若函数()()()224f x x x ax b =-++满足()()2f x f x =-,则()f x 在[]0,3上的最大值为的的_____________二.解答题:本大题共有6道题,共计90分.请在相应的答题区域内作答,解答时应写出文字说明.证明过程或演算步骤.15.已知函数()()[)()sin 0,0,0,2f x A x A ωϕωϕπ=+>>∈图像最高点为(,且相邻两条对称轴间距离为4.(1)求函数()f x 的解析式;(2)求()()()()22221232018f f f f ++++L 的值.16.已知ABC ∆的内角A 、B 、C 所对的边分别为a 、b 、c ,1sin sin B C R+=(其中R 为ABC ∆的外接圆的半径)且ABC ∆的面积()22S a b c =--.(1)求sin A 的值;(2)求ABC ∆的面积S 的最大值.17.已知函数()f x 与()12g x x x=++的图象关于点()1,2A 对称. (1)求函数()f x 的解析式; (2)若函数()()F x f x c =-有两个不同零点,求实数c 的取值范围;(3)若函数()()2a h x f x x =+-在()2,4上是单调减函数,求实数a 的取值范围. 18.某农业观光区的平面示意图如图所示,其中矩形ABCD 的长2AB =千米,宽1AD =千米,半圆的圆心P 为AB 中点,为了便于游客观光休闲,在观光区铺设一条由圆弧»AE 、线段EF 、FC 组成的观光道路,其中线段EF 经过圆心P ,点F 在线段CD 上(不含线段端点C 、D ),已知道路AE 、FC 的造价为每千米20万元,道路EF 造价为每千米70 万元,设APE θ∠=,观光道路的总造价为y .(1)试求y 与θ函数关系式()y f θ=,并写出θ的取值范围;的(2)当θ为何值时,观光道路的总造价y 最小.19.已知函数()24f x ax x b =++(0a <,且a 、b R ∈).设关于x 的不等式()0f x >的解集为()12,x x ,且方程()f x x =的两实根为α、β.(1)若1αβ-=,完成下列问题:①求a 、b 的关系式;②若a 、b 都是负整数,求()f x 的解析式;(2)若12αβ<<<,求证: ()()12117x x ++<.20.已知函数()xf x e ax =-(其中a 为常数,e 为自然对数的底数,) (1)若对任意x ∈R ,不等式()1f x ≥恒成立,求实数a 的取值集合, (2)已知正数a 满足:存在[)01,x ∈+∞,使不等式()00f x ≤成立. ①求a 的取值集合;②试比较a e 与e a 的大小,并证明你的结论.。

推荐-苏州市2018-2018年上学期高三期中考试六校联考数

推荐-苏州市2018-2018年上学期高三期中考试六校联考数

2018-2018学年第一学期高三期中考试数学试卷命题学校:江苏省木渎中学第Ⅰ卷(共60分)一、选择题:本大题共12小题,每小题5分,共60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.与直线240x y -+=平行的曲线4y x =的切线方程是( )A .3208x y -+= B .3208x y --= C .5208x y -+=D .5208x y --=2.设12()nx x x f n n+++=,其中n 是大于1的正整数,若(1)kk x =-,1,2,,k n =,则()f n 的取值集合是( )A .1{1,}n B .1{1,}n - C .1{0,}n D .1{0,}n - 3.已知2211()11x x f x x --=++,则()f x 的解析式可取为( )A .21x x + B .212x x +-C .212x x + D .21x x +-4.已知数列}{n a 中,114a =,54a =,且满足212nn n a a a ++=(1,2,3,n =),则8a =( )A .16B .16±C .32D .32±5.若011<<b a ,则下列不等式:①||||a b >;②ab b a <+;③2>+b a a b ;④22a a bb <-中,正确的不等式有( )A .1个B .2个C .3个D .4个6.已知a 、b 是非零向量且满足(3)a b a -⊥,(4)a b b -⊥ ,则a 与b 的夹角是( )A .6πB .3πC .32πD .65π7.从4名男生和5名女生中任意选出3人参加一个会议,其中至少有1名男生和一名女生,则不同的选派方案有( ) A .140种 B .84种 C .70种 D .35种 8.铜质的球体由于温度的变化,其半径增加了0.1%,则它的体积约增加了( )A .0.1%B .0.2%C .0.3%D .0.4%9.函数12()2x f x =和函数2()2log g x x =的图像的交点个数为( )A .0B .1C .2D .310.设全集{(,)|,U x y xR y R =∈∈,集合{(,)|2A x y x y m =-+>,集合{(,)|B x y x yn =+-≤,那么点(2,3)P A B ∉的充要条件是( )A .1m >-或5n ≥B .1m >-且5n ≥C .1m ≤-或5n <D .1m ≤-且5n <11.定义在区间[,]a b (b a >)上的函数1()sin 2f x x x =的值域是1[,1]2-,则b a -的最大值M 和最小值m 分别是( )A .,63m M ππ==B .2,33m M ππ==C .24,33m M ππ== D .4,23m M ππ==12.若,x R n N ∈∈,定义:(1)(2)(1)nx M x x x x n =+++-,例如:34(4)(3)(2)24M -=---=-,则函数115()sin x f x M x -=⋅的奇偶性是( )A .是偶函数不是奇函数B .是奇函数不是偶函数C .既是奇函数又是偶函数D .既不是奇函数又不是偶函数第Ⅱ卷(共90分)二、填空题:本大题共4小题,每小题4分,共16分.把答案填在题中横线上。

江苏苏州市2018届高三上学期数学期中试卷含解析

江苏苏州市2018届高三上学期数学期中试卷含解析

江苏苏州市2018届高三上学期数学期中试卷(含解析)2017-2018学年江苏省苏州市高三上学期期中调研一、填空题:共14题1.已知集合,则_____.【答案】【解析】由题意,得2.函数的定义域为_____.【答案】【解析】x应该满足:,解得:∴函数的定义域为故答案为:3.设命题;命题,那么p是q的____条件(选填“充分不必要”、“必要不充分”、“充要”、“既不充分也不必要”).【答案】充分不必要【解析】命题q:x2﹣5x+4≥0&#8660;x≤1,或x≥4,∵命题p:x>4;故p是q的:充分不必要条件,故答案为:充分不必要4.已知幂函数在是增函数,则实数m的值是_____.【答案】1【解析】∵幂函数在是增函数∴,解得:故答案为:15.已知曲线在处的切线的斜率为2,则实数a的值是_____.【答案】【解析】f′(x)=3ax2+,则f′(1)=3a+1=2,解得:a=,故答案为:.点睛:与导数几何意义有关问题的常见类型及解题策略(1)已知切点求切线方程.解决此类问题的步骤为:①求出函数在点处的导数,即曲线在点处切线的斜率;②由点斜式求得切线方程为.(2)已知斜率求切点.已知斜率,求切点,即解方程.(3)求切线倾斜角的取值范围.先求导数的范围,即确定切线斜率的范围,然后利用正切函数的单调性解决.6.已知等比数列中,,则_____.【答案】4【解析】设等比数列的公比是q,由a3=2,a4a6=16得,a1q2=2,a1q3a1q5=16,则a1=1,q2=2,∴,故答案为:4.7.函数图象的一条对称轴是,则的值是_____.【答案】【解析】因为函数图象的一条对称轴是,所以,又因为,则,即,解得8.已知奇函数在上单调递减,且,则不等式的解集为_____.【答案】【解析】∵函数f(x)为奇函数且在(﹣∞,0)上单调递减,∴f(x)在(0,+∞)上也单调递减,又∵函数f(x)为奇函数且f(2)=0,∴f(﹣2)=﹣f (2)=0∴不等式等价于①或②解得:x∈(﹣2,0)∪(1,2),故答案为:(﹣2,0)∪(1,2).9.已知,则的值是_____.【答案】【解析】因为,所以====10.若函数的值域为,则实数a的取值范围是_____.【答案】【解析】当时,,则由题意,得当时,成立,则为增函数,且,即11.已知数列满足,则_____.【答案】【解析】∵,,∴,,∴,,归纳猜想:∴故答案为:12.设的内角的对边分别是,D为的中点,若且,则面积的最大值是_____.【答案】【解析】因为,所以,即,即,即,又因为D为的中点,且,所以,即,即,则,则面积的最大值是点睛:三角形中最值问题,一般转化为条件最值问题:先根据正、余弦定理及三角形面积公式结合已知条件灵活转化边和角之间的关系,利用基本不等式或函数方法求最值.在利用基本不等式求最值时,要特别注意“拆、拼、凑”等技巧,使其满足基本不等式中“正”(即条件要求中字母为正数)、“定”(不等式的另一边必须为定值)、“等”(等号取得的条件)的条件才能应用,否则会出现错误.13.已知函数,若对任意的实数,都存在唯一的实数,使,则实数的最小值是___.【答案】【解析】因为,所以,则,因为对任意的实数,都存在唯一的实数,使,所以在上单调,且,则,则,所以,即实数的最小值是点睛:对于方程任意或存在性问题,一般转化为对应函数值域包含关系,即的值域包含于的值域;的值域与的值域交集非空。

推荐-苏州十中高三数学期中试卷2018年2018月 精品

推荐-苏州十中高三数学期中试卷2018年2018月 精品

苏州十中2018—2018学年度第一学期期中考试高三数学试卷 2018.10一、 选择题(12×5’=60’)(做在答题卡上)1、 已知集合M={x|x 2+6x -16>0},N={x|(x ―k)(x ―k ―2)≤0}M ∩N ≠φ,则k 的取值范围是A 、k <-8或k >0B 、k <-8或k >2C 、-8≤k ≤0D 、k ≥0或k ≤-82、 函数f(x)= x 2-2xsin θ+sin θ―1 (θ∈R )的极小值为g(sin θ)则g(sin θ)的最小、最大值是A 、最小值―1,最大值―43 B 、最小值―3,最大值―43 C 、最小值―2,最大值―43 D 、无最小值,最大值―433、 当0≤x ≤1时,函数y=ax+a ―1的值有正值也有负值,则实数a 的取值范围是A 、a <21 B 、a >1 C 、a <21或a >1 D 、21<a <14、 数列{a n }是等比数列,下列结论中正确的是A 、a n a n +1>0B 、a n a n +1 a n +2>0C 、a n a n +2>0D 、a n a n +2 a n +4>0 5、 已知数列{a n }中,a n =1562+n n(n ∈N +),则数列{a n }的最大项是 A 、第12项 B 、第13项 C 、第12项或第13项 D 、不存在6、 将正整数1,2,3,…,n ,…按第k 组含k 个数的规则分组(1),(2,3),(4,5,6),……那么1996所在的组是A 、第62组B 、第63组C 、第64组D 、第65组 7、 角α≠4π是 tan α≠1的_______A 、充分不必要条件B 、必要不充分条件C 、充要条件D 、以上都不对8、 要得到函数y=cos (2x -4π)的图象,只须将函数y=sin2x 的图象A 、向左平移8π个单位B 、向右平移8π个单位C 、向左平移4π个单位 D 、向右平移4π个单位9、关于x 的方程x 2―xcosAcosB ―cos 22c =0有一个根为1,则△ABC 中一定有A 、∠A=∠B B 、∠A=∠C C 、∠B=∠CD 、∠A+∠B=2π10、若a +b +c =0,则a ,b ,cA 、一定可以构成一个三角形B 、一定不可以构成三角形C 、都是非零向量时能构成三角形D 、都是非零向量时也可能无法构成一个三角形 11、设函数f(x)=2sin (2πx +5π),若对任意x ∈R 都为f(x 1)≤f(x)≤f(x 2)成立,则| x 1-x 2|的最小值是A 、4B 、2C 、1D 、2112、在△ABC 中,若sin A=53,cos B=135,则cos C 的值是 A 、6516 B 、6556 C 、6556或6516 D 、-6516高三数学期中考试答题纸一、 选择题(做在答题卡上) 二、填空题(4×4’=16’)13、已知||=2,||=1,且(-k )⊥(-3),⊥,那么k =_________。

2021届江苏省苏州市2018级高三上学期期中考试数学试卷参考答案

2021届江苏省苏州市2018级高三上学期期中考试数学试卷参考答案
2021届江苏省苏州市2018级高三上学期期中考试数学试卷
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2021届江苏省苏州市2018级高三上学期期中考试
数学参考答案
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【最新整理,下载后即可编辑】苏州市2018届高三第一学期期中调研试卷数 学一、填空题(本大题共14小题,每小题5分,共70分,请把答案直接填写在答卷纸...相应的位置) 1.已知集合{1,2,3,4,5},{1,3},{2,3}U A B ===,则()U A B = ▲ .2.函数1ln(1)y x =-的定义域为 ▲ .3.设命题:4p x >;命题2:540q x x -+≥,那么p 是q 的 ▲ 条件(选填“充分不必要”、“必要不充分”、“充要”、“既不充分也不必要”). 4.已知幂函数22*()m m y x m -=∈N 在(0,)+∞是增函数,则实数m 的值是 ▲ .5.已知曲线3()ln f x ax x =+在(1,(1))f 处的切线的斜率为2,则实数a 的值是▲ .6.已知等比数列{}n a 中,32a =,4616a a =,则7935a a a a -=- ▲ .7.函数sin(2)(0)2y x ϕϕπ=+<<图象的一条对称轴是12x π=,则ϕ的值是 ▲ .8.已知奇函数()f x 在(,0)-∞上单调递减,且(2)0f =,则不等式()01f x x >-的解集为 ▲ .9.已知tan()24απ-=,则cos2α的值是 ▲ .10.若函数8,2()log 5,2ax x f x x x -+⎧=⎨+>⎩≤(01)a a >≠且的值域为[6,)+∞,则实数a 的取值范围是 ▲ .11.已知数列{},{}n n a b 满足1111,1,(*)21n n n n a a b b n a +=+==∈+N ,则122017b b b ⋅⋅=▲ .12.设ABC △的内角,,A B C 的对边分别是,,a b c ,D 为AB 的中点,若cos sin b a C c A=+且CD =ABC △面积的最大值是▲ .13.已知函数()sin()6f x x π=-,若对任意的实数5[,]62αππ∈--,都存在唯一的实数[0,]m β∈,使()()0f f αβ+=,则实数m 的最小值是 ▲ . 14.已知函数ln ,0()21,0x x f x x x >⎧=⎨+⎩≤,若直线y ax =与()y f x =交于三个不同的点(,()),(,()),A m f m B n f n(,())C t f t (其中m n t <<),则12n m++的取值范围是 ▲ .二、解答题(本大题共6个小题,共90分,请在答题卷区域内作答,解答时应写出文字说明、证明过程或演算步骤) 15.(本题满分14分)已知函数1())(0,0)42f x ax b a b π=+++>>的图象与x 轴相切,且图象上相邻两个最高点之间的距离为2π.(1)求,a b 的值;(2)求()f x 在[0,]4π上的最大值和最小值.16.(本题满分14分)在ABC △中,角A ,B ,C 所对的边分别是a ,b ,c ,已知sin sin sin ()B C m A m +=∈R ,且240a bc -=.(1)当52,4a m ==时,求,bc 的值;(2)若角A 为锐角,求m 的取值范围.17.(本题满分15分)已知数列{}n a 的前n 项和是n S ,且满足11a =,*131()n n S S n +=+∈N . (1)求数列{}n a 的通项公式;(2)在数列{}n b 中,13b =,*11()n n n na b b n a ++-=∈N ,若不等式2n n a b n λ+≤对*n ∈N 有解,求实数λ的取值范围.如图所示的自动通风设施.该设施的下部ABCD 是等腰梯形,其中AB 为2米,梯形的高为1米,CD 为3米,上部CmD 是个半圆,固定点E 为CD 的中点.MN 是由电脑控制可以上下滑动的伸缩横杆(横杆面积可忽略不计),且滑动过程中始终保持和CD 平行.当MN 位于CD 下方和上方时,通风窗的形状均为矩形MNGH (阴影部分均不通风). (1)设MN 与AB 之间的距离为5(02x x <≤且1)x ≠米,试将通风窗的通风面积S (平方米)表示成关于x 的函数()y S x =;(2)当MN 与AB 之间的距离为多少米时,通风窗的通风面积S 取得最大值?19.(本题满分16分)已知函数2()ln ,()f x x g x x x m ==--. (1)求过点(0,1)P -的()f x 的切线方程;(2)当0=m 时,求函数()()()F x f x g x =-在],0(a 的最大值;(3)证明:当3m ≥-时,不等式2()()(2)e x f x g x x x +<--对任意1[,1]2x ∈均成立(其中e 为自然对数的底数,e 2.718...=).已知数列{}n a 各项均为正数,11a =,22a =,且312n n n n a a a a +++=对任意*n ∈N 恒成立,记{}n a 的前n 项和为n S . (1)若33a =,求5a 的值;(2)证明:对任意正实数p ,221{}n n a pa -+成等比数列;(3)是否存在正实数t ,使得数列{}n S t +为等比数列.若存在,求出此时n a 和n S 的表达式;若不存在,说明理由.2017—2018学年第一学期高三期中调研试卷数学(附加题部分)21.【选做题】本题包括A 、B 、C 、D 四小题,请选定其中两题,并在相..........应的答题区域内作答..........若多做,则按作答的前两题评分.解答时应写出文字说明、证明过程或演算步骤. A .(几何证明选讲)(本小题满分10分)如图,AB 为圆O 的直径,C 在圆O 上,CF AB ⊥于F ,点D 为线段CF 上任意一点,延长AD 交圆O于E ,030AEC ∠=. (1)求证:AF FO =; (2)若CF =,求AD AE ⋅的值.BB .(矩阵与变换)(本小题满分10分)已知矩阵1221⎡⎤=⎢⎥⎣⎦A ,42α⎡⎤=⎢⎥⎣⎦,求49αA 的值.C .(极坐标与参数方程)(本小题满分10分)在平面直角坐标系中,直线l 的参数方程为42525x t y t ⎧=-+⎪⎪⎨⎪=⎪⎩(t 为参数),以原点O为极点,x 轴正半轴为极轴建立极坐标系,圆C 的极坐标方程为cos()(0)4a ρθπ-≠.(1)求直线l 和圆C 的直角坐标方程;(2)若圆C 任意一条直径的两个端点到直线l,求a的值.D .(不等式选讲)(本小题满分10分)设,x y 均为正数,且x y >,求证:2212232x y x xy y ++-+≥.【必做题】第22、23题,每小题10分,共计20分.请在答题卡指定区域.......内作答,解答时应写出文字说明、证明过程或演算步骤. 22.(本小题满分10分)在小明的婚礼上,为了活跃气氛,主持人邀请10位客人做一个游戏.第一轮游戏中,主持人将标有数字1,2,…,10的十张相同的卡片放入一个不透明箱子中,让客人依次去摸,摸到数字6,7,…,10的客人留下,其余的淘汰,第二轮放入1,2,…,5五张卡片,让留下的客人依次去摸,摸到数字3,4,5的客人留下,第三轮放入1,2,3三张卡片,让留下的客人依次去摸,摸到数字2,3的客人留下,同样第四轮淘汰一位,最后留下的客人获得小明准备的礼物.已知客人甲参加了该游戏. (1)求甲拿到礼物的概率;(2)设ξ表示甲参加游戏的轮数..,求ξ的概率分布和数学期望()E ξ.23.(本小题满分10分)(1)若不等式(1)ln(1)x x ax ++≥对任意[0,)x ∈+∞恒成立,求实数a 的取值范围;(2)设*n ∈N ,试比较111231n ++++与ln(1)n +的大小,并证明你的结论.2017—2018学年第一学期高三期中调研试卷数 学 参 考 答 案一、填空题(本大题共14小题,每小题5分,共70分) 1.{1} 2.(1,2)(2,)+∞3.充分不必要 4.15.136.4 7.3π 8.(2,0)(1,2)-9.45-10.(1,2] 11.12018 12.113.2π14.1(1,e )e+二、解答题(本大题共6个小题,共90分) 15.(本题满分14分)解:(1)∵()f x 图象上相邻两个最高点之间的距离为2π,∴()f x 的周期为2π,∴202||2a a ππ=>且,······································································2分∴2a =,··················································································································4分此时1())42f x x b π=+++, 又∵()f x 的图象与x 轴相切,∴1||02b b +=>,·······················································6分∴122b =-;··········································································································8分(2)由(1)可得())4f x x π=+∵[0,]4x π∈,∴4[,]444x ππ5π+∈, ∴当444x π5π+=,即4x π=时,()f x 有最大值为;·················································11分当442x ππ+=,即16x π=时,()f x 有最小值为0.························································14分 16.(本题满分14分) 解:由题意得b c ma+=,240a bc -=.···············································································2分(1)当52,4a m ==时,5,12b c bc +==,解得212b c =⎧⎪⎨=⎪⎩或122b c ⎧=⎪⎨⎪=⎩;································································································6分(2)2222222222()()22cos 23222a ma abc a b c bc a A m a bc bc--+-+--====-,····························8分∵A 为锐角,∴2cos 23(0,1)A m =-∈,∴2322m <<,····················································11分又由b c ma +=可得0m >,·························································································13分∴m <<···········································································14分 17.(本题满分15分)解:(1)∵*131()n n S S n +=+∈N ,∴*131(,2)n n S S n n -=+∈N ≥,∴*13(,2)n n a a n n +=∈N ≥,·························································································2分又当1n =时,由2131S S =+得23a =符合213a a =,∴*13()n n a a n +=∈N ,······························3分∴数列{}n a 是以1为首项,3为公比的等比数列,通项公式为1*3()n n a n -=∈N ; (5)分(2)∵*113()n n n na b b n a ++-==∈N ,∴{}n b 是以3为首项,3为公差的等差数列,····················7分∴*33(1)3()n b n n n =+-=∈N ,·····················································································9分∴2n n a b nλ+≤,即1233n n nλ-⋅+≤,即2133n n n λ--≤对*n ∈N 有解,··································10分设2*13()()3n n nf n n --=∈N ,∵2221(1)3(1)32(41)(1)()333n n nn n n n n n f n f n -+-+---++-=-=, ∴当4n ≥时,(1)()f n f n +<,当4n <时,(1)()f n f n +>, ∴(1)(2)(3)(4)(5)(6)f f f f f f <<<>>>, ∴max 4[()](4)27f n f ==,···························································································14分∴427λ≤.·············································································································15分 18.(本题满分15分)解:(1)当01x <≤时,过A 作AK CD ⊥于K (如上图),则1AK =,122CD AB DK -==,1HM x =-,由2AKMH DKDH ==,得122HM xDH -==,∴322HG DH x =-=+, ∴2()(1)(2)2S x HM HG x x x x =⋅=-+=--+;·······························································4分当512x <<时,过E 作ET MN ⊥于T ,连结EN (如下图),则1ET x =-,22239(1)(1)224MN TN x x ⎛⎫==---- ⎪⎝⎭∴292(1)4MN x =--∴29()2(1)(1)4S x MN ET x x =⋅=---,······································································8分综上:222,01()952(1)(1)142x x x S x x x x ⎧--+<⎪=⎨---<<⎪⎩≤;·································································9分(2)当01x <≤时,2219()2()24S x x x x =--+=-++在[0,1)上递减,∴max ()(0)2S x S ==;································································································11分2︒当512x <<时,229(1)(1)94()2(224x x S x x -+--=-⋅=,当且仅当(1)x -=51(1,)2x +∈时取“=”, ∴max 9()4S x =,此时max 9()24S x =>,∴()S x 的最大值为94,············································14分答:当MN 与AB1+米时,通风窗的通风面积S 取得最大值.····················15分 19.(本题满分16分)解:(1)设切点坐标为00(,ln )x x ,则切线方程为0001ln ()y x x x x -=-, 将(0,1)P -代入上式,得0ln 0x =,01x =, ∴切线方程为1y x =-;·······························································································2分(2)当0m =时,2()ln ,(0,)F x x x x x =-+∈+∞, ∴(21)(1)(),(0,)x x F x x x+-'=-∈+∞,············································································3分当01x <<时,()0F x '>,当1x >时,()0F x '<, ∴()F x 在(0,1)递增,在(1,)+∞递减,·············································································5分∴当01a <≤时,()F x 的最大值为2()ln F a a a a =-+; 当1a >时,()F x 的最大值为(1)0F =;········································································7分(3)2()()(2)e x f x g x x x +<--可化为(2)e ln x m x x x >-+-,设1()(2)e ln ,[,1]2x h x x x x x =-+-∈,要证3m ≥-时()m h x >对任意1[,1]2x ∈均成立,只要证max ()3h x <-,下证此结论成立. ∵1()(1)(e )x h x x x'=--,∴当112x <<时,10x -<,·······················································8分设1()e x u x x=-,则21()e 0x u x x '=+>,∴()u x 在1(,1)2递增, 又∵()u x 在区间1[,1]2上的图象是一条不间断的曲线,且1()202u =<,(1)e 10u =->,∴01(,1)2x ∃∈使得0()0u x =,即01e xx =,00ln x x =-,····················································11分当01(,)2x x ∈时,()0u x <,()0h x '>;当0(,1)x x ∈时,()0u x >,()0h x '<;∴函数()h x 在01[,]2x 递增,在0[,1]x 递减,∴0max 00000000012()()(2)e ln (2)212x h x h x x x x x x x x x ==-+-=-⋅-=--,····························14分∵212y x x=--在1(,1)2x ∈递增,∴0002()121223h x x x =--<--=-,即max ()3h x <-, ∴当3m ≥-时,不等式2()()(2)e xf xg x x x +<--对任意1[,1]2x ∈均成立.··························16分 20.(本题满分16分) 解:(1)∵1423a a a a =,∴46a =,又∵2534a a a a =,∴54392a a ==;·······································2分(2)由3121423n n n n n n n n a a a a a a a a +++++++=⎧⎨=⎩,两式相乘得2134123n n n n n n n a a a a a a a ++++++=,∵0n a >,∴2*42()n n n a a a n ++=∈N , 从而{}n a 的奇数项和偶数项均构成等比数列,···································································4分设公比分别为12,q q ,则1122222n n n a a q q --==,1121111n n n a a q q ---==,······································5分又∵312=n n n na a a a +++,∴42231122a a q a a q ===,即12q q =,···························································6分设12q q q ==,则2212223()n n n n a pa q a pa ---+=+,且2210n n a pa -+>恒成立, 数列221{}n n a pa -+是首项为2p+,公比为q的等比数列,问题得证;····································8分(3)法一:在(2)中令1p =,则数列221{}n n a a -+是首项为3,公比为q 的等比数列,∴22212223213 ,1()()()3(1),11k k k k k k k q S a a a a a a q q q---=⎧⎪=++++++=-⎨≠⎪-⎩, 12122132 ,13(1)2,11k k k k k k k q q S S a q q q q ---⎧-=⎪=-=⎨--≠⎪-⎩,·····································································10分且12341,3,3,33S S S q S q ===+=+,∵数列{}n S t +为等比数列,∴22132324()()(),()()(),S t S t S t S t S t S t ⎧+=++⎪⎨+=++⎪⎩ 即22(3)(1)(3),(3)(3)(33),t t q t q t t q t ⎧+=+++⎪⎨++=+++⎪⎩,即26(1),3,t q t t q +=+⎧⎨=-⎩ 解得14t q =⎧⎨=⎩(3t =-舍去),·························································································13分∴224121k k k S =-=-,212121k k S --=-, 从而对任意*n ∈N 有21n n S =-, 此时2n n S t +=,12n n S tS t-+=+为常数,满足{}n S t +成等比数列, 当2n ≥时,111222n n n n n n a S S ---=-=-=,又11a =,∴1*2()n n a n -=∈N , 综上,存在1t =使数列{}n S t +为等比数列,此时1*2,21()n n n n a S n -==-∈N . (16)分法二:由(2)知,则122n n a q -=,121n n a q --=,且12341,3,3,33S S S q S q ===+=+,∵数列{}n S t +为等比数列,∴22132324()()(),()()(),S t S t S t S t S t S t ⎧+=++⎪⎨+=++⎪⎩ 即22(3)(1)(3),(3)(3)(33),t t q t q t t q t ⎧+=+++⎪⎨++=+++⎪⎩,即26(1),3,t q t t q +=+⎧⎨=-⎩ 解得14t q =⎧⎨=⎩(3t =-舍去),·······················································································11分∴121222n n n a q --==,22212n n a --=,从而对任意*n ∈N 有12n n a -=,····································13分∴01211222222112n n n n S --=++++==--, 此时2n n S t +=,12n n S tS t-+=+为常数,满足{}n S t +成等比数列, 综上,存在1t =使数列{}n S t +为等比数列,此时1*2,21()n n n n a S n -==-∈N . (16)分21.【选做题】本题包括A 、B 、C 、D 四小题,请选定其中两题,并在相..........应的答题区域内作答..........若多做,则按作答的前两题评分.解答时应写出文字说明、证明过程或演算步骤. A .(几何证明选讲,本小题满分10分) 解:(1)证明 :连接,OC AC ,∵030AEC ∠=,∴0260AOC AEC ∠=∠=,又OA OC =,∴AOC ∆为等边三角形, ∵CF AB ⊥,∴CF 为AOC ∆中AO 边上的中线, ∴AF FO =;····························B··········································5分(2)解:连接BE , ∵CF =,AOC ∆是等边三角形,∴可求得1AF =,4AB =,∵AB 为圆O 的直径,∴90AEB ∠=,∴AEB AFD ∠=∠, 又∵BAE DFA ∠=∠,∴AEB ∆∽AFD ∆,∴AD AF ABAE=,即414AD AE AB AF ⋅=⋅=⨯=.··················································································10分 B .(矩阵与变换,本小题满分10分) 解:矩阵A 的特征多项式为212()2321f λλλλλ--==----, 令()0f λ=,解得矩阵A 的特征值121,3λλ=-=,····························································2分当11λ=-时特征向量为111α⎡⎤=⎢⎥-⎣⎦,当23λ=时特征向量为211α⎡⎤=⎢⎥⎣⎦,·····································6分又∵12432ααα⎡⎤==+⎢⎥⎣⎦,·························································································。

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