2019-2020年新疆乌鲁木齐市二模:乌鲁木齐市2019届高三第二次模拟考试理综物理试题-含答案

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新疆维吾尔自治区乌鲁木齐市2019届高三第二次诊断性测试语文试卷附答案解析

新疆维吾尔自治区乌鲁木齐市2019届高三第二次诊断性测试语文试卷附答案解析

2019年高三年级第二次诊断性测试语文试卷(卷面分值:150分;考试时间:150分钟)注意事项:1.本试卷为问答分离式试卷,由问卷和答题卡(答卷)两部分组成,答案务必写或涂在指定位置上。

2.答题前,请考生务必将自己的学校、姓名、准考证号、科别等信息填写在答题卡(答卷)的密封区内。

一、现代文阅读(36分)(一)论述类文本阅读(本题共3小题,9分)阅读下面的文字,完成各题。

庄子和尼采是处于不同历史时代的哲学家,虽然处于不同的历史背景之下,但相似的是,二人都对各自的文化传统进行了批判,并作出自己的价值重估,着重强调人的精神自由。

”庄子的哲学是批判宗法制礼教文化对人性的束缚,强调对人的精神自由的追求。

他认为“人为”和“自为”两种因素束缚着人,使人不得自由,他对儒家的“圣人”说,仁义礼智及当时的社会关系进行了猛烈的攻击。

尼采生活在19世纪的德国,基督教教义影响着人们的价值观念。

同时,资本主义开始发展,机器生产带来物质繁荣,人异化成机器的奴隶。

欧洲陷入了前所未有的信仰危机和价值危机。

尼采的哲学是建立在希腊悲剧精神的重建以及反基督教文化之上的。

他认为基督教是人追求精神自由的最大阻碍,因此他对基督教进行了批判,认为一切价值需重新评判,每个人都必须自己作人生的决定和命运的抉择。

庄子身处动荡变迁之时,战乱频繁,死亡时刻威胁人类。

人生是苦难的,生命如白驹过隙,短暂易逝,世人对死亡充满畏惧。

庄子为人们提供了一种在这样的生活环境中求得内心平静的方法,即站在道的角度看待生死,超越生与死的界限,视生死为大道的自然造化,顺其自然,将自身与道融为一体,从而达到心灵的宁静。

“死生,命也。

其有夜旦之常,天也。

人之有所不得与,皆物之情也。

”社会充满凶险,生命朝不保夕,如何才能在“方今之时,仅免于刑”的社会中保身呢?庄子告诉我们“直木先伐,甘井先竭”,有才能的人劳苦奔忙,结果往往“中于机辟,死于网罟”,所以只有像庖丁的解牛刀一样巧妙地避免与社会发生碰撞,才能够活得自由。

乌鲁木齐地区2019年高三年级第二次诊断性测验数学(理)试卷

乌鲁木齐地区2019年高三年级第二次诊断性测验数学(理)试卷

乌鲁木齐地区2019年高三年级第二次诊断性测验理科数学试卷注意事项:本卷分为问卷和答卷两部分,答案务必写在答卷的指定位置处第Ⅰ卷(选择题,共60分)一、选择题(共12小题,每小题5分,共60分. 每小题的四个选项中,只有一项是符合题目要求的,请将正确答案填在答卷的相应位置上) 1.复数3-i(3+i )2=A. - 12B. 12 C. 2i - D. 2i2.设a ,b 为两条直线,α、β为两个平面. 下列四个命题中,不正确...的是 A. a ∥b , b ⊥α⇒a ⊥α B. a ⊥α, a ∥β⇒α⊥βC.,α∥β, a ⊥α⇒a ⊥βD. α⊥β, a ∥α⇒a ⊥β 3.若a , b 是整数,则“a +b 是偶数”是“a 2-b 2是偶数”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.已知等边三角形ABC 的边长为1,且→BC = a ,→AC = b ,则|a +b |= A.32B. 1C. 3D. 2 5.圆x 2+y 2=1上的点到两坐标轴的距离之积的最大值是A. 12B. 22C. 1D. 26.盒中有10个螺丝钉,其中有3个是坏的,现从盒中随机的抽取4个,那么恰有2个是好螺丝钉的概率等于A. 12B. 310C. 710D. 20461047. 已知函数f (x )=lo g 3 1x ,则f (1-1x)>1的解集是A. (0, 32 )B. (1, 32) C. (1, 3 ) D. (0, 3 )8.有两个大小一样的球,其中一个球的球心在另一个球的球面上,且这两个球的交线长为 3π,则球的半径是A. 1B. 2C. πD. 2π 9设f (x )=x sin x , 当x 1 , x 2∈[-π2,π2]时,f (x 1)>f (x 2)成立,则下列结论正确的是A. x 1>x 2B. x 1>|x 2|C. x 1<x 2D. x 12>x 2210. 若点P 在平面区域⎩⎪⎨⎪⎧x ≥0y-1≥0x+y-2≤0 上,点Q 在曲线(x -2)2+y 2=1上,则|PQ |的取值范围是A. [2-1, 2+1]B. [2-1, 5]C.[ 1, 7]D. [2-1,22+1]11.某钝角三角行三边长分别为k , k +1, k +2,则k 的取值范围是A. (0, 3)B. (1, 2 )C. (1, 3 )D. (2, 3 )12. F 1, F 2是双曲线22221x y a b-= (a , b >0)的左、右焦点,过点F 1作一斜率为k 的直线,交双曲线右支于点P ,且∠F 1PF 2为锐角,M 为线段F 1P 的中点,过坐标原点O 作OT ⊥F 1P 于点T ,且|OM | - |TM |=b -a ,则k = A. b a B. a b C. a a 2+b 2 D. b a 2+b 2第Ⅱ卷(非选择题 共90分)二、填空题(共4小题,每小题5分,共20分)(请将正确答案直接填在答卷中相应各题的横线上)13. 集合A ={3, lo g 2a }, B ={a , b },若A ∩B =={1},则A ∪B = ;14. 已知( x 2+1x3 )n 展开式中只有第六项的二项式系数最大,则展开式中常数项为 (用数字作答).15. 若直线y = 12x 关于y =x 对称的直线与抛物线y =-x 2-2x +m 相交于两点A 、B ,则线段AB的中点坐标是 . 16. 数列{a n }中,a 1=5, 11n a ⎧⎫⎨⎬+⎩⎭是等差数列,且53111116a a =+++,则数列{a n }中是整数的各项之和等于 .三、解答题(共6小题,共70分)解答应在答卷的相应各题中写出文字说明、证明过程或演算步骤.17.(本题满分10分)已知函数f (x )=2sin(x +π4)co s (x-π4) .(Ⅰ)求f (π8)的值;(Ⅱ)若f (x ) = 12在[0, π]上有两个根x 1, x 2 ,且x 1<x 2 ,求f (x 2-x 1)的值如图所示,已知ABCD是正方形,PC⊥平面ABCD,AB=1,PC=2.(Ⅰ)求异面直线PB与AC所成角的大小;P(Ⅱ)在线段P A上确定一点E,使PB⊥平面CDE,并求出此时平面CDE与底面ABCD所成二面角的大小.C BD A19.(本题满分12分)甲、乙两名篮球运动员的投篮命中率分别为35和25(且相互独立),现每人投篮2次,记ξ为甲进球数减去乙进球数,求ξ的概率分布及数学期望.20.(本题满分12分)设数列{a n}的前n项和为S n,且S n+a n=n-1n(n-1)(n∈N*).(Ⅰ)求a1 , a2;(Ⅱ)证明{S n-1n+1}是等比数列,并写出{a n}的通项公式;(Ⅲ)当n≥2时,求a nS n的最大值在平面直角坐标系中,已知点A 1(-a , 0)、A 2(a , 0)、P (0, bt )、Q (a-at , b ),直线A 1P 与A 2Q 的交点为G ,其中a >b >0.(Ⅰ)当t 变化时,求交点G 的轨迹方程;(Ⅱ)设c =F (c , 0 ),G 的轨迹与y 轴相交于点B 1、B 2,直线B 1F 交直线A 2B 2于M 点、交G 的轨迹于N 点,若11B M B N λ=u u u u r u u u u r,求λ的取值范围22.(本题满分12分)求函数f (x )= e ax x-a (a < 12)在[2, 3 ]上的最大值和最小值.乌鲁木齐地区2019年高三年级第二次诊断性测验理科数学试题参考答案及评分标准1.选C.【解析】()22i i i iiii====-.2.选D.【解析】αβ⊥,a∥αa⇒与β可能平行、相交,或aβ⊂,故命题D错误.3.选C.【解析】∵()()22a b a b a b-=+-,,a b是整数,若a b+是偶数,则()()a b a b+-是偶数;若()()a b a b+-是偶数,则a b+,a b-中至少有一个偶数,若a b-是偶数,必有,a b同为奇数或同为偶数,此时仍有a b+是偶数.4.选C.【解析】设O是AB的中点,连接CO,()()22CO====u u u ra b a b+-+-5.选A.【解析】∵x y⋅≤22122x y+=,当且仅当2x y==时取等号.6.选B.【解析】恰有2个是好螺丝钉的概率等于2273410310C CC=.7.选B.【解析】3331111log1log log331111x xfx x xx⎛⎫->⇒>⇒>⇒>⎪--⎝⎭-,231xx-⇒<-()()3123012x x x⇒--<⇒<<.8.选A.【解析】于是在由r、12r、Rt△中可得1r=.9.选D.【解析】∵()()()f x f x f x-==,又()()12f x f x>,∴()()12f x f x>∵当0≤x ≤2π时,()f x 单调递增,∴12x x >,即2212x x >. 10. 选D .【解析】在坐标平面画出题中的不等式组表示的平面区域,结合图形,可知PQ 的最小值是点()1,1与圆心()2,0的距离减去半径1,1;PQ 的最大值是点()0,2与圆心()2,0的距离加半径1,即1.11.选C .【解析】由已知得210k k k +>+>>,设此三角形最大边2k +所对角为θ,此三角形为钝角三角形,故只能是角θ为钝角,∴()()()22212cos 21k k k k k θ++-+=+()223021k k k k --=<+,即03k <<,又cos 1θ≠-且()12k k k ++>+,解得13k <<.12.选B .【解析】连结2PF ,∵O 是线段12F F 的中点,M 为线段1F P 的中点.∴212OM PF =且OM ∥2PF ,∴11290F MO F PF ∠=∠<︒ ∴点T 在线段1F M 上, 而111112MT F M FT F P FT =-=-, ∴()2112111111222OM TM PF F P FT PF F P FT a FT -=-+=-+=-+,又OM TM b a -=-,∴1FT b =,OT a ===.∴11tan OT ak OFT FT b =∠==. 二、填空题(共4小题,每小题5分,共20分)13.填{}1,2,3.【解析】由{}1A B =I 知2log 12a a =⇒=,于是只有1b =.14.填210.【解析】由已知得10n =.由()1022051101031rrrr rr T C xC xx --+⎛⎫== ⎪⎝⎭, 令2050r -=,得4r =,常数项为4510210T C ==.15.填(2,4)--.【解析】直线12y x =关于y x =对称的直线为2y x =代人抛物线方程中得 240x x m +-=,1222x x x +==-,12122()422y y x x y ++===-,故线段AB 的中点坐标为(2,4)--.16.填11.【解析】由题意知11n a ⎧⎫⎨⎬+⎩⎭的首项11116a =+,公差d 有531112116d a a =-=++,即112d =,∴()111111111212n n n a a +=+-⋅=++, ∴1211n a n =-+,要使n a 是整数,需12能被1n +整除,而n ∈*N ,故1,2,3,5,11n =,所以12351111a a a a a ++++=.三、解答题(共6小题,共70分) 17.(Ⅰ)∵()22222sin cos cos sin f x x x x x ⎛⎫⎛⎫=++⎪⎪ ⎪⎪⎝⎭⎝⎭()2sin cos x x =+1sin 2x =+. …2分∴21sin 21882f ππ⎛⎫⎛⎫=+⨯=+⎪ ⎪⎝⎭⎝⎭; …5分 (Ⅱ)由题意有1()1sin 22f x x =+=1sin 22x ⇒=-, ∵[]0,x π∈,∴[]20,2x π∈,于是726x π=,或1126x π=,解得1712x π=,21112x π=,∴213x x π-=,则()21231sin 1332f x x f ππ⎛⎫-==+=+⎪⎝⎭. …10分 18. 解法一(Ⅰ)过B 作P B '∥PC 且使BP '=PC ,连结AP CP ''、.于是有PB ∥P C ',∴ACP '∠即为异面直线PB 与AC 所成的角.由已知条件易知AB ⊥平面PBP C ',且3PB P C '==,2AC =.在Rt △ABP '中,22221(2)3,P A AB P B ''=+=+=在△ACP '中,由余弦定理得222cos 2AC P C P A ACP AC P C ''+-'∠='⋅66223==⨯⨯, 故异面直线PB 与AC 所成的角为6arccos; …6分 (Ⅱ)过C 作CF PB ⊥于点F ,过F 作FE ∥AB 交PA 于点E ,连结CE ,FE ∥AB ∥DC ,而DC PB ⊥,这样确定的点E ,可使PB ⊥平面CDE .在Rt △PBC 中,由1122CF PB PC BC ⋅=⋅ 得 263CF ==,在Rt △PCF中,23PF PB ====, 在Rt △PAB 中,∵FE ∥AB ,∴23PE PA =. 即 23PE PA =时,PB ⊥平面CDE . 由已知条件易知DC ⊥平面PBC ,∴FC DC ⊥,BC DC ⊥, 即BCF ∠是平面CDE 与底面ABCD 所成二面角的平面角,在Rt △BCF中,cos CF BCF BC ∠== 故平面CDE 与底面ABCD所成二面角的大小为 …12分 解法二如图建立空间直角坐标系C xyz -,则(0,0,0),(1,1,0),(0,1,0),(0,0C A B P .(Ⅰ)(0,1,)PB =u u u r ,(1,1,0)CA =u u u r,∴cos ,PB CA PB CA PB CA⋅〈〉===u u u r u u u ru u u r u u u r u u u r u u u r 故异面直线PB 与AC所成的角为arccos6…6分 (Ⅱ)假设在PA 上存在E 点,使PB ⊥平面CDE ,记PE PA λ=u u u r u u u r,∵(1,1,PA =u u u r,∴(,,)PE λλ=u u u r,∴(,)CE λλ=u u u r , 由PB CE ⊥⇔01)320PB CE λλλ⋅=⨯+⨯=-=u u u r u u u r ,∴23λ=.即 23PE PA =时,PB CE ⊥,而PB CD ⊥,故PB ⊥平面CDE .由PB ⊥平面CDE ,PC ⊥底面ABCD,(0,0,PC =u u u r,可得cos ,3PB PC PB PC PB PC⋅〈〉===u u u r u u u ru u u r u u u r u u u r u u u r , 故平面CDE 与底面ABCD所成二面角的大小为arccos3. …12分19. ξ可取的值为2,1,0,1,2--. …2分223216(2)155625P ξ⎛⎫⎛⎫=-=-⨯=⎪ ⎪⎝⎭⎝⎭; 22112232332296(1)1555555625P C C ξ⎛⎫⎛⎫=-=-⨯⨯⨯+⨯⨯⨯=⎪ ⎪⎝⎭⎝⎭; 2222112232322332216(0)1155555555625P C C ξ⎛⎫⎛⎫⎛⎫⎛⎫==-⨯-+⨯⨯⨯⨯⨯+⨯=⎪ ⎪ ⎪ ⎪⎝⎭⎝⎭⎝⎭⎝⎭; 221122323323216(1)555555625P C C ξ⎛⎫⎛⎫==⨯⨯⨯+⨯⨯⨯=⎪ ⎪⎝⎭⎝⎭; 223281(2)155625P ξ⎛⎫⎛⎫==⨯-=⎪ ⎪⎝⎭⎝⎭. ∴ξ的分布列为169621681221126256256256255E ξ=-⨯-⨯+⨯+⨯=. …12分 20.(Ⅰ)当1n =时,由110S a +=得120a =,∴10a =,当2n =时,2216S a +=,得2126a =,解得2112a =; …2分 (Ⅱ)当n ≥2时,由1n n n a S S -=-代人1(1)n n n S a n n -+=+中,得:1111212(1)1(1)1n n n S S n n n n n n n---==-=-++++,∴11121n n S S n n -⎛⎫-=- ⎪+⎝⎭,且11122S -=-, 所以11n S n ⎧⎫-⎨⎬+⎩⎭是首项为12-,公比为12的等比数列.即111111222n n nS n -⎛⎫-=-=-⎪+⎝⎭⇒ 1112n n S n =-+,于是 1(1)n n n a S n n -=-+111(1)12n n n n n -=-+++112(1)n n n =-+; …6分(Ⅲ)由(Ⅱ)当n ≥2时,11111111112(1)122211*********12n n n n n nn nna n n n n n S n n n --⎛⎫⎛⎫----- ⎪ ⎪++⎝⎭⎝⎭===----+++, 由111211112(11)1n n n n n n C C C ------=+=++++L ≥n ,得n ≥2时,12n -≥n 恒成立,即1112n n --≥0成立,当且仅当2n =时取等号. 而当n ≥2时,11012n n ->+恒成立, 所以111211112n n nnan S n --=--+≤1,当且仅当2n =时等号成立.故nna S 的最大值为1. …12分 21. (Ⅰ)当0t =时,直线1A P :0y =,直线2A Q :x a =,交点(,0)G a ; 当0t ≠时,直线1A P :()bt y x a a =+,直线2A Q :()by x a at=--, 则动直线1A P 与2A Q 的交点(,)G x y 满足2()bt y x a a =+()b x a at ⎛⎫⋅-- ⎪⎝⎭2222()b x a a =--,整理得:22221x y a b +=,其中0a b >>,又点(,0)G a 也满足此式. 综上知交点G 的轨迹方程22221(0)x y a b a b+=>>. …6分(Ⅱ)不妨设1(0,)B b 、2(0,)B b -,由1;2,1.x y ac bc ab c b M x y a c a c a b⎧+=⎪-⎪⎛⎫⇒⎨ ⎪++⎝⎭⎪+=⎪-⎩. 2222222222222221;210101.x y x a a c b b x a b a b x x c c c x y a b ⎧+=⎪⎛⎫⎪⎛⎫⇒+--=⇒+-=⎨ ⎪ ⎪⎝⎭⎝⎭⎪+=⎪⎩. 2222N a cx a c ⇒=+,由 11B M B N λ=u u u u r u u u u r M N x x λ⇒=,2222121211M N x a c e e x a ac e e λ++⇒====++-+++.又01e <<,∴112e <+<,设1t e =+,(1,2)t ∈,而函数()t λ在(是减函数;在)2上是增函数.∴2≤2221211t e t e +-=++-<+,∴)2,1λ⎡∈⎣. …12分22. (1)若0a =,则1()f x x=在[2,3]单调递减,∴()min 3y f =;()max 2y f =; (2)若0a ≠,由()()()()()221axaxaxa x a e aex a ea f x x a x a x a ⎛⎫-- ⎪--⎝⎭'==≠--,①当,则∵[2,3](,)a ⊂+∞,∴()f x 在[2,3]单调递减,()min 3y f =;()max 2y f =;由已知及重要不等式,有22a a a<<<+,若1a a+≥3,即0a <12<时,()f x 在[2,3]单调递减, ()min 3y f =;()max 2y f =;若13a a +<12a <<,此时有11232a a a<<<+<, 而()()()()()32232233232a a aa e e e f f a e a a a a a ⎡⎤-=-=-+-⎣⎦----.令()()312322tg t t e t t ⎛⎫=-+-<<⎪ ⎪⎝⎭,则()()11tg t t e '=-+. 设()()11th t t e =-+,则()0th t te '=-<,故()h t 单调递减,∴()()12111022g t h t h e ⎛⎫'=>=+> ⎪⎝⎭,故()g t 单调递增.()12135351.650.025022222g t g e ⎛⎫<=-<⨯-=-< ⎪⎝⎭,即()()32f f <,即min 1y f a a ⎛⎫=+⎪⎝⎭;()max 2y f =.综上:当a ≤()3min 33a e y f a ==-,()2max 22ae yf a==-;当3122a <<时,21min 1a y f a ae a +⎛⎫=+= ⎪⎝⎭;()2max 22a e y f a ==-. …12分以上各题的其它解法,限于篇幅,从略.请相应评分.。

2019-2020学年乌鲁木齐市实验学校高三英语二模试卷及答案

2019-2020学年乌鲁木齐市实验学校高三英语二模试卷及答案

2019-2020学年乌鲁木齐市实验学校高三英语二模试卷及答案第一部分阅读(共两节,满分40分)第一节(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的A、B、C、D四个选项中选出最佳选项ABest Places to Visit in JulyNorway's FjordsMost travelers prefer to visit Norway's famous fjords (峡湾) in July because Norway has about 23 hours of daylight, giving travelers lots of time to take in the spectacular views of blue water, glaciers and mountains. July is also whenNorway's weather is at its warmest, about18℃, so travelers might include a light sweater in their luggage.Bastille Day inParisJuly 14 is a national day celebrating independence to the French. July 14, 1789, is the day the French stormed the Bastille, aParisprison, and officially began the French Revolution, overthrowing a royal government that often threw people in prison there for no reason at all. While the day is marked all overFrance, the biggest celebration takes place inParis.Masai Mara National ReserveThe thrill of seeing millions of animals wander the plains inKenyais not easily forgotten. One of the most popular months to visit the Masai Mara is in July when the famous wildlife migration reaches the Masai Mara and zebras are at their highest number. The best times to view the animals inKenya's most popular game park are dawn and dusk.Running of the Bulls inPamplonaTravelers who pride themselves on being fast runners may want to head toPamplonain July for the San Femin Festival. A key part of this annual festival is the running of the bulls. Six bulls are released onto a narrow street fora half-mile run, with hundreds of runners seeing if they can run faster than the animals.1. What can visitors do inNorway's in July?A. Enjoy the impressive scenery.B. Swim and fish in the fjords.C. See daylight around the clock.D. Buy heavy sweaters to keep warm.2. Which of the following is of historical significance?A. San Fermin Festival.B. Bastille Day.C. Masai Mara National Reserve.D.Norway's Fjords.3. Where will visitors interested in wild animals go?A. Norway.B. Paris.C. Masai Mara.D.Pamplona.BDid you know people who live in different parts ofChinahave different habits and preferences? For example, people from southernChinaprefer to eat vegetables, while people from northChinalike to eat meat. According to a new study in a journal, gene variations (变异) might be responsible for these differences. Researchers fromChina’s BGI collected genetic information from 141,431 Chinese women, who came from 31 provinces and consisted of 36 ethnic minority groups.They found that natural selection has played an important role in the ways that people living in different regions of China have developed, affecting their food preferences, immunities (免疫力) to illness and physical features.A variation of the gene FADS2 is more commonly found in northern people. It helps people metabolize (新陈代谢) fatty acids, which suggests a diet that is rich in flesh. This is due to climate differences.Northern Chinais at a higher latitude. This weather is difficult to grow vegetables in. Therefore, northerners tend to eat more meat.The study also found differences in the immune systems of both groups. Most people in southernChinacarry the gene CR1, which protects against malaria. Malaria was once quite common in southernChina. In order to survive, the genes of people in the south evolved to fight against this disease. However, people in the south are also more sensitive to certain illnesses, as they lack the genes to stop them.Genes can also cause physical differences between northerners and southerners. Most northerners have the ABCC11 gene, which causes dry earwax, less body smell and fewer sweats. These physical differences are also more beneficial to living in cold environments. Southerners are less likely to have this gene, as it did not develop in their population.4. What did the new study focus on?A. Regions.B. Eating habits.C. Gene variations.D. Ethnic minority groups.5. What is the main function of the gene FADS2?A. It helps store fat.B. It helps digest meat.C. It helps gain weight.D. It helps treat an illness.6. According to the study, most northerners ________.A. sweat less frequentlyB. are immune to malariaC. prefer vegetables to meatD. are more sensitive to climates7. How many differences did the study find related to genes?A. Two.B. Three.C. Four.D. Five.CByteDance(字节跳动)Group’s TikTok, an overseas version of Chinese short video sharing app Douyin, faces an existential crisis in the United States, as murmurs of a “crackdown”(强制取缔)from the White House forced the Chinese company toengage in talks on selling its US business to Microsoft.TikTok is the fastest-growing registered global mobile internet app, with more than 100 million users, and its rapid growth, especially in the US, is seen as a threat to Facebook. The US government has long viewed globally competitive Chinese high-tech companies including Huawei as a threat and done whatever it could to crack down on(打击)them in the name of “national security”.The US government has not introduced any specific policy against TikTok only threatened it through a number of unclear statements.According to the latest media reports, Microsoft is prepared to press ahead withthe negotiations to take over TikTok’s US operations and complete the negotiations by Sept 15, following talks between Microsoft CEO Satya Nadella and US President Donald Trump.This means that TikTok will have to hand its fate over to some unpredictable power, and even have to sell its assets without the option of setting a price.The US government has failed to find a reasonable legal excuse to deal with TikTok. All private data of TikTok’s US users are stored in the US and are unlikely to be transferred. Considering the US government is trying to deal with TikTok in a political way, TikTok should consider incorporating(合并)the dispute into the US legal process to assert(坚持)its legal rights and interests.TiKTok’s core value lies in its unique algorithms,a product of artificial intelligence that represents the expertise of Chinese engineers and programmers with high-value intellectual property.The US government’s move, which has forced ByteDance to sell TikTok to a US company, is similar to a forced technology transfer and an example of the US’ openseizureof Chinese intellectual property.If ByteDance sells TikTok to a US company for “security reasons", that would set a dangerous precedent, motivating other countries where TikTok operates to follow the US administration's example and cause a chainreaction.ByteDance is a young Chinese private company that cannot deal with a political game played by the US. But as a Chinese company that has gone global, ByteDance has reasons to take up legal means to defend its legal rights. The Chinese government can also consider examining whether the technology transfer in the deal violates China’s law and harms the country’s national interests.8. What is the most valuable as for TikTok?A. Its global popularity.B. Its artificial intelligence.C. Its registered global mobile internet app.D. Its private data of TikTok’s worldwide users.9. Why does the American government force the Chinese company to hand over TikTok’s US operations to a US company?A. Out of so-called political reasons.B. Out of so-called debt reasons.C. Out of so-called technical reasons.D. Out of so-called security reasons.10. What does the underlined word “seizure”probably mean in Para. 8?A. An untrue spoken statement about someone.B. The use of legal authority to take sth from sb.C. The crime of stealing sth from a person or place.D. The act of trying to hurt somebody using physical violence.11. What can be the best title for the news report?A. TikTok must defend its rights legallyB. TikTok is seen as a threat to FacebookC. ByteDance has to sell TikTok to a US companyD. ByteDance agrees to transfer technologyDHappiness is not a warm phone, according to anew study exploring the link between young life satisfaction and screen time. The study was led by professor of psychology Jean M. Twenge at San Diego State University (SDSU).To research this link, Twenge, along with colleagues Gabrielle Martin at SDSU and W. Keith Campbell at the University of Georgia, dealt with data from the Monitoring the Future (MtF) study, a nationally representativesurvey of more than a million U. S. 8th-, 10th-, and 12th-graders. The survey asked students questions about how often they spent time on their Phones, tablets and computers, as well as questions about their face-to-face social interactions and their overall happiness.On average found that teens who spent more time in front of screen devices — playing computer games, using social media, texting and video chatting — were less happy than those who invested more time in non-screen activities like sports, reading newspapers and magazines, and face-to-face social interactions."The key to digital media use and happiness is limited use," Twenge said. "Aim to spend no more than two hours a day on digital media, and try to increase the amount of time you spend seeing friends face-to-face and exercising — two activities reliably linked to greater happiness."Looking at historical trends from the same age groups since the 1990s, it's easy to find that the increase of screen devices over time happened at the same time as a general drop-off in reported happiness inU. S.teens. Specifically, young peopled life satisfaction and happiness declined sharply after 2012. That's the year when the percentage of Americans who owned a smartphone rose above 50 percent. By far the largest change in teens' lives between 2012 and 2016 was the increase in the amount of time they spent on digital media, and the following decline in in-person social activities and sleep.12. Which method did Twenge's team use for the study?A. Calculating students' happiness.B. Asking students certain questions.C. Analyzing data from a survey.D. Doing experiments on screen time.13. How does the author develop the finding of the study in paragraph 3?A. By making a comparison.B. By giving an example.C. By making an argument.D. By introducing a concept.14. What is the purpose of the last paragraph?A. To draw a conclusion from the study.B. To offer some advice to the readers.C. To prove social activities' importance.D. To support the researchers' finding.15. Which of the following can be the best title for the text?A. Quitting Phones Equals HappinessB. Screen Time Should Be BannedC. Teens' Lives Have Changed SharplyD. Screen-addicted Teens Are Unhappier第二节(共5小题;每小题2分,满分10分)阅读下面短文,从短文后的选项中选出可以填入空白处的最佳选项。

2019-2020学年乌鲁木齐市高级中学高三英语二模试卷及参考答案

2019-2020学年乌鲁木齐市高级中学高三英语二模试卷及参考答案

2019-2020学年乌鲁木齐市高级中学高三英语二模试卷及参考答案第一部分阅读(共两节,满分40分)第一节(共15小题;每小题2分,满分30分)阅读下列短文,从每题所给的A、B、C、D四个选项中选出最佳选项AShopping centers,stadiums and universities may soon have a new tool to help fight crime.ACaliforniacompany called Knightscope says its robots can predict and prevent crime. Knightscope says the goal is to reduce crime by half in areas the robots guard.William Santana Li is the chief executive officer of Knightscope. He says,"These robot security guards will change the world. Our planet has more than seven billion people on it. It's going to quickly get to nine billion people. The security equipmentthat we have globally is just not going to develop that fast. The company's Autonomous Data Machines can become the eyes and ears of law enforcement(执法).""You want them to be machines plus humans. Let. the machines do the heavy and sometimes dangerous work and let the humans do the strategic decision-making work,so it's always working all together."The machines do not carry weapons but they have day and night video cameras which are able to turn 360 degrees and can also sense chemical and biological weapons.Some people may become concerned about their privacy, especially in connection with the video recordings. Some people may worry that such recordings will appear on the Internet. Eugene Volokh, a law professor at the UCLA School of Law, says the machines have to be used in the right way and it will be interesting to see how state laws deal with this kind of video.William Santana Li says there is a long waiting list for the robots in theUS. Workers in the company are working overtime to meet the demands of the market. At least 25 other countries are also interested in these robot security guards.1. What can this new tool do for humans?A. Make strategic decisions.B. Keep watching day and night.C. Carry heavy weapons.D. Stop crime autonomously.2. Why are some people worried about the new robots?A. Their privacy may be let out.B. The robots are very expensive.C. Robots will replace humans.D. They will be out of work soon.3. Which of the following can be the best title of the text?A. Robots Are Becoming More PopularB. Robots Contribute aLotto the WorldC. Robots Are in Great Demand NowD. Security Robots Could Help Cut CrimeBI got my first bike when I was nine years old. Jimmy, the bike, was my first love. I rode it everywhere. The suburb, the back lanes, the fields and forests, the river paths and swampland were far more exciting than any adventure novel or television series.There’s nothing quite like the relationship between a child and his bicycle and the endless happiness two wheels and a pair of strong legs offer. No video or computer game can replace the liberation of being alone on a bicycle.As parents, to deny children the simple pleasure of riding a bike is a failure of our responsibilities to raise independent and stable young citizens. We should offer our children a healthy alternative to hours in front of an addictive screen. Studies have shown that cycling promotes not only muscle growth but brain growth. Guess which country has children with the best mental health outcomes and is regularly the top of listings of the happiest young people. No surprise it’s theNetherlands, the unquestioned leader among industrial countries in encouraging bicycle use.Our dependence on cars has degraded the public transport system, polluted our sky, led to the untimely death of thousands every year, and denied children safe access to their suburbs. A recent study found that 69% of children were accompanied to school. The same study found that a similar number of parents drove to work.In some regions ofJapan, when children start their first year of school, parents are expected to walk with them for the first few weeks, introducing them to residents and shopkeepers along the chosen route, letting the community take care of these children. However, driving children to school isproscribed. Children can choose to ride a bike or walk to school after they are familiar with the community, and it’s the community’s role to keep them safe.Therefore, I strongly advise the government to provide better infrastructure (基础设施). Build separatedcycle lanes, decrease speed limits, and design street scapes that favour people over cars. The results will be less pollution, quieter suburbs, a healthier population and, best of all, happy and independent children.4. What can we infer about the author from the text?A. He was addicted to computer games.B. He liked taking adventurous trips in nature.C. He had great fun exploring the outside by cycling.D.He got his first birthday present at the age of nine.5. Why does the author mention theNetherlandsin Paragraph 3?A. To introduce his good way of raising independent children.B. To illustrate the great influence riding has on mental health.C. To stress the importance of being physically and mentally healthy.D. To explain cycling does best in city development in theNetherlands.6. What does the underlined word “proscribed” in Paragraph 5 probably mean?A. Recommended.B. Protected.C. Delayed.D. Forbidden.7. How does the author mainly support his idea?A. By analyzing causes.B. By listing examples.C.By giving definitions.D. By analyzing scientific data.CIt was once a shoreline buried by enough garbage to make it invisible (看不见的), thus, given the unfortunate nickname "toilet bowl" . Now the Philippines' Manila Bay beach is totally different, compared with a few months ago. It happened so suddenly and extremely that it brought tears to the eyes of the local people.The cleanup started on 27 January, when 5, 000 volunteers descended on Manila Bay to remove over 45 tons (公吨) of garbage, marking the beginning of a nation-wide environmental campaign. But some two months before this great movement began, a quiet revolution was already underway.During the first week of December 2018, Brooklyn- based Bounties Network collectedthree tons of garbage from Manila Bay aver two days through a project that paid a small group of people, mostly fishermen, with a digital currency (数字货币) based on the Ethereum system.For the mostly non-bank -using Filipino fishermen, this was a first-ever experience with a digital currency. It's one that proves decisive in enabling poor communities around the world to take up arms in the fight against humanity's waste.There are signs that this recycling-for-digital payment industry may be just about to take off. Earlier in September 2018, Plastic Bank, a Vancouver -based company powered by IBM technology, also started a similar project. They set up a project in Naga, a town in southern Luzon, the country's largest island, building a collection point to let people exchange plastic and recyclable materials for digital payouts through a system.That both these pioneers have chosen the Philippines as their first location is not surprising considering the country's contribution to ocean waste. A Wall Street Journal study in 2015 revealed that the Philippines make the third-largest amount of plastic waste into global oceans.8. Why did people call Manila Bay beach“toilet bowl” ?A. It looked like a huge bowl.B. There were plenty of toilets.C. It was covered by rubbish.D. People loved the toilets here.9. What does the underlined phrase“descended on”in paragraph 2 mean?A. Completely depended on.B. Suddenly arrived at.C. Occasionally decreased to.D. Gradually disappeared from.10. What made poor communities willing to fight against waste?A. The benefits to their homeland.B. The desire to make a difference.C. The chance to escape ocean pollution.D. The experience with a digital currency.11. What is the best title for the text?A. Online system helps endocean pollution.B. Manila Bay beach is suddenly removed.C. Plastic Bank is powerful in recycling waste.D. Philippines make a great amount of waste.DOver the years, NASA has successfully sent several rovers (飞行器) to Mars. While the science laboratories continue to provide important information on the Red Planet, they keep the space exploration rovers staying closeto the original landing place.To get a more comprehensive (详尽的) view of Mars, the US Space Agency plans to make a small test helicopter with the Mars 2020 Rover, which will be sent off in July 2020.The football-sized “marscopter” weighs about four pounds.It can fly at about ten times the speed of helicopters on Earth. The light weight and fast speed are important for the helicopter to be able to fly in the thin Mars atmosphere, which is about just one percent of that of Earth. “To make it fly in that thin Mars atmosphere, we had to make everything ready, and make it as light as possible while being as strong and powerful as it canpossibly be. “Mimi Aung, Mars helicopter project manager, said in a meeting.Upon landing on the Red Planet, the Mars 2020 Rover will find a proper location to send of the helicopter. The helicopter will start with a short climb, no higher than 10 feet, and hover (盘旋) for just 30 seconds before landing back on the Mars surface. If all goes well, five more flights of longer distances, for 90 seconds each, will be conducted over the next 30 days. The short journeys will be recorded by a small camera and sent back to the scientists on Earth.If the plan goes on well, the first helicopter to fly in another world, will open up a whole new way to explore Mars. The Mars helicopter's first flight will be a great invention. For those of us whose research is about flight, that would be a wonderful, historic moment.12. To fly in thin Mars atmosphere,we should make the helicopter_______.A. strong and heavyB. heavy and fastC. light and fastD. strong and slow13. How many times will the helicopter fly?A. Three timesB. Four timesC. Five timesD. Six times14. What can we learn from the last paragraph?A. It’s interesting to fly in another world.B. I' s important to fly in another world.C. The plan to fly the helicopter goes on well.D. The helicopters first flight is successful.15. What may be the best title for the passage?A. To send a helicopter to Mars in 2020B. To send a rover to Mars in 2020C. To live in the thin Mars atmosphereD. To send back records to scientists第二节(共5小题;每小题2分,满分10分)阅读下面短文,从短文后的选项中选出可以填入空白处的最佳选项。

新疆乌鲁木齐地区2019届高三第二次质量监测数学(理)试题(解析版)

新疆乌鲁木齐地区2019届高三第二次质量监测数学(理)试题(解析版)

新疆乌鲁木齐地区2019届高三第二次质量监测数学(理)试题注意事项:1.答卷前,考生务必用黑色字迹的钢笔或签字笔在答题卡上填写自己的准考证号、姓名、试室号和座位号。

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一、选择题(本大题共12小题,共60.0分)1.设集合A={x|x<1},B={x|x2<4},则A∩B等于()A. {x|−2<x<1}B. {x|1<x<2}C. {x|−1<x<2}D. {x|x<2}2.已知复数z=2−i1+i(i是虚数单位),则复数z的虚部为()A. −32B. −32i C. 12D. 12i3.图象关于原点对称且在定义域内单调递增的函数是()A. f(x)=cosx−1B. f(x)=x2+2C. f(x)=−1xD. f(x)=x34.若实数x,y满足{x−4y+3≤03x+5y−25≤0x≥1,则函数z=2x+y的最大值为()A. 12B. 325C. 3D. 155.我国南北朝时期数学家、天文学家祖暅提出了著名的祖暅原理:“幂势既同,则积不容异”.其中“幂”即是截面积,“势”是几何体的高,意思是两等高立方体,若在每一等高处的截面积都相等,则两立方体的体积相等,已知某不规则几何体与如图所示的几何体满足“幂势同”,则该不规则几何体的体积为()A. 4−π2B. 8−π C. 8−4π3D. 8−2π6.已知实数a=2ln2,b=2+2ln2,c=(ln2)2,则a,b,c的大小关系是()A. c<a<bB. c<b<aC. b<a<cD. a<c<b7.如图所示算法框图,当输入的x为1时,输出的结果为()A. 3B. 4C. 5D. 68.已知F1,F2是双曲线x2-y2=1的焦点,以F1F2为直径的圆与一条渐近线交于P,Q两点,则△F1PQ的面积为()A. √22B. 1C. √2D. 29.若关于x的方程(sin x+cos x)2+cos2x=m在区间[0,π)上有两个根x1,x2,且|x1-x2|≥π4,则实数m的取值范围是()A. [0,2)B. [0,2]C. [1,√2+1]D. [1,√2+1)10. 设F 1,F 2分别是椭圆C :x 2a 2+y 2b 2=1(a >b >0)的左、右焦点,直线l 过F 1交椭圆C于A ,B 两点,交y 轴于C 点,若满足F 1C ⃗⃗⃗⃗⃗⃗⃗ =32AF 1⃗⃗⃗⃗⃗⃗⃗ 且∠CF 1F 2=30°,则椭圆的离心率为( )A. √33B. √36C. 13D. 1611. 已知A ,B ,C 为球O 的球面上的三个定点,∠ABC =60°,AC =2,P 为球O 的球面上的动点,记三棱锥p 一ABC 的体积为V 1,三棱銋O 一ABC 的体积为V 2,若V 1V 2的最大值为3,则球O 的表面积为( )A.16π9B.64π9C. 3π2D. 6π12. f (x )的定义域是(0,+∞),其导函数为f ′(x ),若f ′(x )-f(x)x=1-ln x ,且f(e )=e 2(其中e 是自然对数的底数),则( )A. f(2)<2f(1)B. 4f(3)<3f(4)C. 当x >0时,f(x)>0D. 当x >0时,f(x)−ex ≤0 二、填空题(本大题共4小题,共20.0分) 13. 在(x2+√x 3)8的展开式中,常数项为______.14. 已知sin (π6-α)=14,则cos (2α+2π3)的值为______.15. 在平面直角坐标系xOy 中,若直线y =x +m 与曲线y =a sin x +b cos x (a ,b ,m ∈R )相切于点(0,1),则a+b m的值为______.16. 如图,在圆内接四边形ABCD 中,已知对角线BD 为圆的直径,AB =AC =2√2,AD =1.则AC ⃗⃗⃗⃗⃗ ⋅BD⃗⃗⃗⃗⃗⃗ 的值为______. 三、解答题(本大题共7小题,共82.0分)17. 记公差不为零的等差数列{a n }的前n 项和为S n ,已知a 1=2,a 4是a 2与a 8的等比中项.(Ⅰ)求数列{a n }的通项公式;(Ⅱ)求数列{1S n}的前n 项和T n .18. 如图,在四棱锥P -ABCD 中,底面ABCD 是边长为2的菱形,∠DAB =60°,PD =4,M 为PD 的中点,E 为AM 的中点,点F 在线段PB 上,且PF =3FB . (Ⅰ)求证EF ∥平面ABCD ;(Ⅱ)若平面PDC ⊥底面ABCD ,且PD ⊥DC ,求平面PAD 与平面PBC 所成锐二面角的余弦值.19. 某互联网公司为了确定下季度的前期广告投入计划,收集了近6个月广告投入量x(单位:万元)和收益y (单位:万元)的数据如表:月份 1 2 3 4 5 6 广告投入量 24 6 8 10 12 收益14.2120.3131.831.1837.8344.67他们分别用两种模型①y =bx +a ,②y =ae bx 分别进行拟合,得到相应的回归方程并进行残差分析,得到如图所示的残差图及一些统计量的值;x −y −∑6i=1x i y i∑6i=1xi 27301464.24364(Ⅰ)根据残差图,比较模型①,②的拟合效果,应选择哪个模型?并说明理由; (Ⅱ)残差绝对值大于2的数据被认为是异常数据,需要剔除: (i )剔除异常数据后求出(Ⅰ)中所选模型的回归方程: (ⅱ)若广告投入量x =18时,该模型收益的预报值是多少?附:对于一组数据(x 1,y 1),(x 2,y 2),…,(x n ,y n ),其回归直线=x +的斜率和截距的最小二乘估计分别为:=∑(n i=1x i −x −)(y i −y −)∑(n i=1x i −x −)2=∑x i ni=1y i −−yn x −∑x i 2n i=1−n x−2,=y −-x −.20. 已知拋物线C :x 2=2py 经过点P (2,1),其焦点为F ,M 为抛物线上除了原点外的任一点,过M 的直线l 与x 轴、y 轴分别交于A ,B 两点. (Ⅰ)求抛物线C 的方程以及焦点坐标;(Ⅱ)若△AMF 与△ABF 的面积相等,证明直线l 与抛物线C 相切.21. 已知函数f (x )=e x +xtx−1(其中e 是自然对数的底数).(Ⅰ)当t =0时,求f (x )的最值;(Ⅱ)若t ≠0时,f (x )在(1t ,+∞)上的最小值为1,求实数t 的取值范围.22. 在平面直角坐标系xOy 中,曲线C 1的参数方程为{y =3−t x=t,(t 为参数),在以坐标原点为极点,x 轴非负半轴为极轴的极坐标系中,曲线C 2的极坐标方程为ρ=4sinθ.(Ⅰ)写出C 1的普通方程和C 2的直角坐标方程;(Ⅱ)若C 1与C 2相交于A ,B 两点,求△OAB 的面积.23. 已知函数f (x )=2|x +1|-|x -a |,a ∈R .(Ⅰ)当a =1时,求不等式f (x )<0的解集;(Ⅱ)若关于x 的不等式f (x )<x 有实数解,求实数a 的取值范围.答案和解析1.【答案】A【解析】解:由B中不等式解得:-2<x<2,即B={x|-2<x<2},∵A={x|x<1},∴A∩B={x|-2<x<1},故选:A.求出B中不等式的解集确定出B,找出A与B的交集即可.此题考查了交集及其运算,熟练掌握交集的定义是解本题的关键.2.【答案】A【解析】解:复数z====.复数的虚部为:-.故选:A.通过复数的乘除运算法则化简求解复数为:a+bi的形式,即可得到复数的虚部,本题考查复数的代数形式的混合运算,复数的基本概念,是基本知识的考查.3.【答案】D【解析】解:根据题意,函数的图象关于原点对称,则该函数为奇函数,据此分析选项:对于A,f(x)=cosx-1,为偶函数,不符合题意;对于B,f(x)=x2+2,为偶函数,不符合题意;对于C,f(x)=-,是奇函数,但在其定义域中不是单调函数,不符合题意;对于,f(x)=x3,是奇函数即其图象关于原点对称且在定义域内单调递增,符合题意;故选:D.根据题意,依次分析选项中函数的奇偶性与单调性,综合即可得答案.本题考查函数的奇偶性与单调性的判定,关键是掌握常见函数的奇偶性与单调性,属于基础题.4.【答案】A【解析】解:作出不等式组对应的平面区域如图:(阴影部分).由z=2x+y得y=-2x+z,平移直线y=-2x+z,由图象可知当直线y=-2x+z经过点A时,直线y=-2x+z的截距最大,此时z最大.由,解得,即A(5,2),代入目标函数z=2x+y得z=2×5+2=12.即目标函数z=2x+y的最大值为12.故选:A.作出不等式组对应的平面区域,利用目标函数的几何意义,即可求最大值.本题主要考查线性规划的应用,利用目标函数的几何意义,结合数形结合的数学思想是解决此类问题的基本方法.5.【答案】B【解析】解:由题意可得,几何体是正方体挖去一个半圆柱,如图:故它的体积为(4-)×2=8-π,故选:B.根据三视图,可得该几何体是正方体挖去一个半圆柱,利用三视图的数据求解即可.本题主要考查祖暅原理,利用三视图求几何体的体积,属于基础题.6.【答案】A【解析】解:易知1<2ln2<2,2+2ln2>2,0<(ln2)2<1,∴c<a<b.故选:A.利用指数与对数函数的单调性即可得出.本题考查了指数与对数函数的单调性,考查了推理能力与计算能力,属于基础题.7.【答案】C【解析】解:当x=1时,x>1不成立,则y=x+1=1+1=2,i=0+1=1,y<20不成立,x=2,x>1成立,y=2x=4,i=1+1=2,y<20成立,x=4,x>1成立,y=2x=8,i=2+1=3,y<20成立,x=8,x>1成立,y=2x=16,i=3+1=4,y<20成立x=16,x>1成立,y=2x=32,i=4+1=5,y<20不成立,输出i=5,故选:C.根据程序框图,利用模拟验算法进行求解即可.本题主要考查程序框图的识别和判断,利用模拟运算法是解决本题的关键.8.【答案】C【解析】解:F1,F2是双曲线x2-y2=1的焦点,F1(-,0),以F1F2为直径的圆与一条渐近线交于P,Q两点,|PQ|=2c=2,左焦点到渐近线x=y的距离为:d==1,所以则△F1PQ的面积为:=.故选:C.求出双曲线的渐近线方程,求出焦距,左焦点到渐近线的距离,然后求解三角形的面积.本题考查双曲线的简单性质的应用,三角形的面积的求法,考查计算能力.9.【答案】A【解析】解:关于x的方程(sinx+cosx)2+cos2x=m在区间[0,π)上有两个根x1,x2,方程即sin2x+cos2x=m-1,即sin(2x+)=,∴sin(2x+)=在区间[0,π)上有两个根x1,x2,且|x1-x2|.∵x∈[0,π),∴2x+∈[,),∴-≤<,求得0≤m<2,故选:A.直接利用三角函数关系式的恒等变换,把函数的关系式变形成正弦型函数,进一步利用函数的性质求出结果.本题主要考查三角恒等变换,正弦函数的图象和性质,属于中档题.10.【答案】A【解析】解:设F1,F2分别是椭圆的左、右焦点,F1,(-c,0).直线l过F1交椭圆C于A,B两点,交y轴于C点,若满足且∠CF1F2=30°,可得C(0,),则(c,)=(-c-x,-y),解得A(,-).可得:即:,e∈(0,1).解得e=.故选:A.利用已知条件求出C与A的坐标,把A点的坐标代入椭圆方程即可求出椭圆的离心率.本题考查椭圆的简单性质的应用,是基本知识的考查.11.【答案】B【解析】解:如图,设△ABC的外接球球心为O′,其半径为r,球O的半径为R,由题意可知,=3,可得R=,∵2r==,∴r=,∴,∴=,当球心O在三棱锥P-ABC外时,结果不变.故选:B.根据题意作出图形关键部分,利用同底三棱锥体积比等于高的比可得R,r之间的关系,由正弦定理可得r,问题得解.此题考查了球内接几何体,同底三棱锥体积比等于高的比,正弦定理等,难度适中.12.【答案】D【解析】解:构造函数,则=,对其两边积分得,又f(e)=e2得,所以,即,令t=lnx,则二次函数的对称轴为t=1,即x=e,且图象开口向下,g(2)>g(1),即,故f(2)>2f(1),所以A项错误;g(3)>g(4),所以4f(3)>3f(4),故B项错误;根据开口向下的二次函数的图象可知,当x>0时,f(x)>0不正确,故C项错误;当x>0时,要使f(x)-ex≤0成立,只需成立,显然二次函数在对称轴t=1处取得最大值e,很明显成立,故D项正确;故选:D.构造函数,则=,对其两边积分结合条件f(e)=e2的解析式,采用换元法,借助二次函数的图象与性质进行分析、求解.本题综合考查了导数运算法则、积分、二次函数的性质,是一道综合性很强的题目.13.【答案】7【解析】解:二项展开式的通项为令解得r=6∴展开式的常数项为故答案为:7利用二项展开式的通项公式求出通项,令x的指数为0求出r的值,将其值代入通项求出展开式的常数项.解决二项展开式的特定项问题,利用的工具是二项展开式的通项公式.14.【答案】−78【解析】解:cos(2)=-cos(-2α)=-1+2sin2(-α)=-1+2×=.故答案为:-.利用诱导公式以及二倍角公式化简求解即可.本题考查二倍角的三角函数,诱导公式的应用,考查计算能力.15.【答案】2【解析】解:根据题意,若直线y=x+m与曲线y=asinx+bcosx(a,b,m∈R)相切于点(0,1),则点(0,1)为直线y=x+m与y=asinx+bcosx的交点,则有,解可得m=1,b=1,又由y=asinx+bcosx,则y′=acosx-bsinx,又由y′|x=0=acos0-bsin0=1,解可得a=1,则==2;故答案为:2.根据题意,分析可得点(0,1)为直线y=x+m与y=asinx+bcosx的交点,则有,解可得m、b的值,求出y=asinx+bcosx,利用导数的几何意义分析可得y′|x=0=acos0-bsin0=1,解可得a的值,将a、b、m的值代入中计算可得答案.本题考查利用导数分析曲线的切线方程,关键是掌握导数的几何意义,属于基础题.16.【答案】−409【解析】解:在Rt△ABD中,,所以BD=3,∴.在△ABC中,由余弦定理可知,AB2=AC2+BC2-2AC•BCcos∠ACB,即,解之得.在Rt △BCD 中,,所以==.故答案为:.先在Rt △ABD 中求出cos ∠ADB ,cos ∠ABD ,然后在△ABC 中根据余弦定理求出BC ,再在Rt △BCD 中求出 cos ∠CBD ,进而利用数量积计算的值.本题主要考查圆的性质、余弦定理、平面向量的数量积运算,综合性较强,难度较大.17.【答案】解:(Ⅰ)由已知,a 42=a 2⋅a 8,即(2+3d )2=(2+d )(2+7d ),解得:d =2(d ≠0), ∴a n =2+2(n -1)=2n ; (Ⅱ)由(Ⅰ)得,S n =2n +n(n−1)×22=n(n +1),∴1S n=1n(n+1)=1n −1n+1,∴T n =(1−12)+(12−13)+⋯+(1n −1n+1)=1−1n+1=nn+1. 【解析】(Ⅰ)由等差数列的性质列式求得公差,则通项公式可求;(Ⅱ)由(Ⅰ)写出等差数列的前n 项和,取倒数,再由裂项相消法求解. 本题考查等差数列的通项公式及前n 项和,训练了裂项相消法求数列的前n 项和,是中档题.18.【答案】证明:(Ⅰ)取MD 的中点N ,连结EN ,FN ,∵E 为AM 的中点,∴EN ∥AD ,又∵M 为PD 的中点,N 为MD 的中点,∴PN =3ND , ∵PF =3FB ,∴FN ∥BD ,∵EN ∩FN =N ,AD ∩BD =D , ∴平面ENF ∥平面ABCD ,∵EF ⊂平面ENF ,∴EF ∥平面ABCD .解:(Ⅱ)∵平面PDC ⊥平面ABCD ,PD ⊥DC ,∴PD ⊥平面ABCD ,设AB 的中点为G ,以D 为坐标原点,DG 为x 轴,DC 为y 轴,DP 为z 轴,建立空间直角坐标系,则B (√3,1,0),C (0,2,0),P (0,0,4),则BC ⃗⃗⃗⃗⃗ =(-√3,1,0),CP⃗⃗⃗⃗⃗ =(0,-2,4), 设平面PBC 的法向量n⃗ =(x ,y ,z ), 则{n ⃗ ⋅BC ⃗⃗⃗⃗⃗ =−√3x +y =0n⃗ ⋅CP ⃗⃗⃗⃗⃗ =−2x +4z =0,取x =2,得n⃗ =(2,2√3,√3), 同理得平面PAD 的法向量m⃗⃗⃗ =(√3,3,0), 设平面PAD 与平面PBC 所成锐二面角为θ,则cosθ=|n ⃗⃗ ⋅m ⃗⃗⃗ ||n ⃗⃗ |⋅|m ⃗⃗⃗ |=4√1919, ∴平面PAD 与平面PBC 所成锐二面角的余弦值为4√1919.【解析】(Ⅰ)取MD 的中点N ,连结EN ,FN ,推导出EN ∥AD ,FN ∥BD ,从而平面ENF ∥平面ABCD ,由此能证明EF ∥平面ABCD .(Ⅱ)设AB 的中点为G ,以D 为坐标原点,DG 为x 轴,DC 为y 轴,DP 为z 轴,建立空间直角坐标系,利用向量法能求出平面PAD 与平面PBC 所成锐二面角的余弦值.本题考查线面平行的证明,考查二面角的平面角的余弦值的求法,考查空间中线线、线面、面面间的位置关系等基础知识,考查运算求解能力,考查数形结合思想,是中档题.19.【答案】解:(Ⅰ)由于模型①残差波动小,应该选择模型①;(Ⅱ)(i )剔除异常数据,即组号为3的数据,剩下数据的平均数为x −=15(7×6-6)=7.2,y −=15(30×6-31.8)=29.64; ∑x i 5i=1y i −5x −y −=206.4,∑x i 25i=1−5x −2=68.8.∴,=29.64-3×7.2=8.04.∴所选模型的回归方程为;(ⅱ)若广告投入量x =18时,该模型收益的预报值是3×18+8.04=62.04. 【解析】(Ⅰ)根据残差图分析,得出模型①残差波动小,故选模型①;(Ⅱ)(i )剔除异常数据,计算剩下数据的平均数,求出回归系数,写出回归方程;(ⅱ)把x=18代入回归方程,即可求得该模型收益的预报值. 本题考查线性回归方程的求法,考查计算能力,是中档题.20.【答案】解:(Ⅰ)∵抛物线x 2=2py 过点P (2,1),∴4=2p ,解得p =2,∴抛物线的方程为x 2=4y ,其焦点坐标为( 0,1),(Ⅱ)设(x 0,x 024),由△AFM 的面积等于△AFB 的面积,可得|MA |=|AB |,即A 是MB 的中点,∴A (x 02,0),B (0,-x 024),∴直线l 的方程为y =x 02(x -x 02), 直线l 的方程与抛物线C 的方程联立得{y =x 02(x −x 02)x 2=4y,得x 2-2x 0x +x 02=0,得x =x 0,y =x 024, ∴直线l 与抛物线C 只有一个公共点, ∴直线l 与抛物线相切,且切点为M . 【解析】(Ⅰ)把P (2,1)代入抛物线可得p=2和焦点坐标; (Ⅱ)设(x 0,),由△AFM 的面积等于△AFB 的面积,可得|MA|=|AB|,由此求出 A ,B 的坐标后得直线l 的方程,再联立直线与抛物线解得交点只有一个M ,故相切.本题考查了抛物线的性质,属中档题.21.【答案】解:(Ⅰ)当t =0时,f (x )=e x -x ,则f ′(x )=e x -1令f ′(x )>0解得x >0,函数f (x )在(0,+∞)是增函数;令f ′(x )<0,解得x <0,函数f (x )在(-∞,0)是减函数; 所以f (x )有最小值,无最大值,且f (x )max =f (0)=1. (Ⅱ)当t >0时,由x >1t ,所以tx -1>0,f(x)=e x +xtx−1=e x +1t +1t(tx−1)>e x +1t >1+1t >1,不符合题意; 当t <0时,f′(x)=e x −1(tx−1)2=e x(tx−1)2[(tx −1)2−e −x ].令g (x )=(tx -1)2-e -x (x >1t ),易知y =(tx -1)2,y =-e -x 在(1t ,+∞)上均为增函数, 所以g (x )=(tx -1)2-e -x (x >1t )在(1t ,+∞)上也为增函数,且g (0)=0, 当1t <x <0时f ′(x )<0,当x >0时,f ′(x )>0, 故f (x )min =f (0)=1,符合题意; 所以实数t 的取值范围为(-∞,0). 【解析】(Ⅰ)先利用导数判断单调性,从而确定最值的存在情况,求出最值; (Ⅱ)对t 分类讨论,再根据最小值为1的条件,确定实数t 的取值范围. 本题考查了函数的最值,同时考查了分类讨论思想,属于中档题目. 22.【答案】解:(Ⅰ)∵曲线C 1的参数方程为{y =3−t x=t,(t 为参数),∴C 1的普通方程为x +y -3=0,∵曲线C 2的极坐标方程为ρ=4sinθ,即ρ2=4ρsinθ, ∴C 2的直角坐标方程为x 2+y 2-4y =0.(Ⅱ)原点O 到直线x +y -3=0的距离为d =3√2,C 2的标准方程为x 2+(y -2)2=4,表示圆心为C 2(0,2),半径r =2的圆, C 2到直线x +y -3=0的距离d 2=√22,∴|AB |=2√r 2−d 22=√14, ∴S △OAB =d2⋅|AB|=12×√14×√2=3√72.【解析】(Ⅰ)由曲线C 1的参数方程能求出C 1的普通方程,曲线C 2的极坐标方程转化为ρ2=4ρsinθ,由此能求出C 2的直角坐标方程. (Ⅱ)原点O 到直线x+y-3=0的距离为d=,C 2的标准方程为x 2+(y-2)2=4,表示圆心为C 2(0,2),半径r=2的圆,C 2到直线x+y-3=0的距离d 2=,求出|AB|=2=,由此能求出△OAB 的面积.本题考查曲线的普通方程、直角坐标方程的求法,考查三角形面积的求法,考查极坐标方程、参数方程、直角坐标方程的互化等基础知识,考查运算求解能力,是中档题.23.【答案】解:(Ⅰ)当a =1时,f (x )=2|x +1|-|x -1|,当x <-1时,由f (x )<0得-2(x +1)+(x -1)<0,即-x -3<0,得x >-3,此时-3<x <-1,当-1≤x ≤1,由f (x )<0得2(x +1)+(x -1)<0,即3x +1<0,得x <-13,此时-1≤x <-13, 当x >1时,由f (x )<0得2(x +1)-(x -1)<0,即x +3<0,得x <-3,此时无解, 综上-3<x <-13,(Ⅱ)∵f (x )<x ⇔2|x +2|-x <|x -a |有解,等价于函数y =2|x +2|-x 的图象上存在点在函数y =|x -a |的图象下方,由函数y=2|x+2|-x与函数y=|x-a|的图象可知:a>0或a<-4.【解析】(Ⅰ)分3段去绝对值解不等式组,再相并;(Ⅱ)f(x)<x⇔2|x+2|-x<|x-a|有解,等价于函数y=2|x+2|-x的图象上存在点在函数y=|x-a|的图象下方,根据图象写出结果.本题考查了绝对值不等式的解法,属中档题.。

新疆乌鲁木齐2019-2020学年高三年级第二次诊断性测试理科数学试题(解析版)

新疆乌鲁木齐2019-2020学年高三年级第二次诊断性测试理科数学试题(解析版)

2020年高三年级第二次诊断性测试理科数学(问卷)(卷面分值:150分;考试时间:120分钟)第Ⅰ卷(选择题共60分)一、选择题:本大题共12小题,每小题5分,在每个小题给出的四个选项中,只有一项是符合题目要求的. 1.设全集U=R ,{}2|280A x x x =-->,则U A =ð( )A. {4x x >或}2x <- B. {2x x ≤-或}4x ≥C.{}|24x x -<<D.{}|24x x -≤≤【答案】D 【解析】 【分析】利用一元二次不等式的解法求出集合A ,再利用补集的定义求出U A ð即可.【详解】因为不等式2280x x -->的解集为{4x x >或}2x <-, 所以集合A ={4x x >或}2x <-,由补集的定义可知,U Að={}|24x x -≤≤.故选:D【点睛】本题考查一元二次不等式的解法和补集的定义;考查运算求解能力;属于基础题. 2.设i 为虚数单位,复数z 满足()314z i i +=,则在复平面内,z 对应的点位于( )A. 第一象限B. 第二象限C. 第三象限D. 第四象限【答案】A 【解析】 【分析】化简1z i =-,故1z i =+,得到答案.【详解】()314zi i +=,则()()()()32144122111i i iiz i i i i i --====--+-+--+,故1z i =+.故对应的点位于第一象限. 故选:A .【点睛】本题考查了复数的化简,共轭复数,复数对应象限,意在考查学生的计算能力和综合应用能力.3.已知α是第二象限角,且31cos 24πα⎛⎫+=⎪⎝⎭,则cos α=( ) A. 154-B.14- C.14D.154【答案】A 【解析】 【分析】利用诱导公式和同角三角函数的基本关系进行化简求值即可. 【详解】因为31cos 24πα⎛⎫+=⎪⎝⎭,由诱导公式可得,1sin 4α=,因为22sin cos 1αα+=,α是第二象限角, 所以2115cos 1sin 1164αα=--=--=-.故选:A【点睛】本题考查三角函数的诱导公式和同角三角函数的基本关系;考查运算求解能力;属于中档题.4.我们正处于一个大数据飞速发展的时代,对于大数据人才的需求也越来越大,其岗位大致可分为四类:数据开发、数据分析、数据挖掘、数据产品.某市2019年这几类工作岗位的薪资(单位:万元/月)情况如下表所示:由表中数据可得该市各类岗位的薪资水平高低情况为( ) A. 数据挖掘>数据开发>数据产品>数据分析 B. 数据挖掘>数据产品>数据开发>数据分析 C. 数据挖掘>数据开发>数据分析>数据产品 D 数据挖掘>数据产品>数据分析>数据开发【答案】B 【解析】 【分析】计算每个岗位的平均工资,比较得到答案.【详解】数据开发的平均工资为:1.58% 2.525% 3.532% 4.535% 3.44⨯+⨯+⨯+⨯=; 数据分析的平均工资为:1.515% 2.536% 3.532% 4.517% 3.01⨯+⨯+⨯+⨯=; 数据挖掘的平均工资为:1.59% 2.512% 3.528% 4.551% 3.71⨯+⨯+⨯+⨯=; 数据产品的平均工资为:1.57% 2.517% 3.541% 4.535% 3.54⨯+⨯+⨯+⨯=; 故数据挖掘>数据产品>数据开发>数据分析. 故选:B .【点睛】本题考查了数据的平均值,意在考查学生的计算能力和应用能力.5.双曲线22 C: 2x y -=的右焦点为F ,点P 为C 的一条渐近线上的点,O 为坐标原点.若||||PO PF =,则∆=OPF S ( )A.14B.12C. 1D. 2【答案】C 【解析】 【分析】由双曲线方程得到渐近线方程,以及右焦点坐标,再由||||PO PF =,求出P 点坐标,进而可求出三角形面积. 【详解】因为双曲线方程为22C:2x y -=, 所以其渐近线方程为y x =±,右焦点为(2,0)F , 因为点P 为C 的一条渐近线上的点,不妨设点P 在y x =上,且点P 在第一象限;又||||PO PF =,所以∆POF 为等腰三角形, 所以点P 横坐标为1,因此(1,1)P , 所以112∆=⋅=OPF p S OF y . 故选C【点睛】本题主要考查双曲线中的三角形面积问题,熟记抛物线的简单性质即可,属于常考题型. 6.已知ABC V 是边长为4的等边三角形,D 为AB 的中点,以CD 为折痕,将ABC V 折成直二面角A CDB --,则过A ,B ,C ,D 四点的球的表面积为( )A. 18πB. 20πC.22πD.24π【答案】B 【解析】 【分析】如图所示:易知DA ,DB ,DC 两两垂直,E 为BC 中点,F 为AD 中点,故球心O 在平面BCD 的投影为E ,2225R EO DE =+=,计算表面积得到答案.【详解】如图所示:易知DA ,DB ,DC 两两垂直,E 为BC 中点,F 为AD 中点, 故球心O 在平面BCD 的投影为E ,OFAD ⊥,122DE BC ==,112OE DF AD ===, 设球半径为R ,则在Rt ODE △中:2225R EO DE =+=,故2420S R ππ==. 故选:B .【点睛】本题考查了三棱锥的外接球问题,意在考查学生的计算能力和空间想象能力. 7.下列函数是偶函数,且在()0,∞+上是增函数的是( )A. ()ln f x x =B.()12f x x=C.()1f x x x=-D. ()3xf x =【答案】D 【解析】 【分析】利用偶函数的定义、幂函数、指数函数和对数函数的单调性进行逐项判断即可. 【详解】对于选项A :因为()ln f x x =,所以其定义域为()0,∞+,不关于原点对称,所以函数()ln f x x=为非奇非偶函数,故选项A 排除; 对于选项B :因为()12f x x =x =,所以其定义域为[)0,+∞,不关于原点对称,所以函数()12f x x=为非奇非偶函数,故选项B 排除;对于选项C :因为()1f x x x=-,所以其定义域为{}0x x ≠关于原点对称, 因为()()11f x x x f x x x ⎛⎫-=--=--=- ⎪-⎝⎭,所以函数()1f x x x =-为奇函数, 故选项C 排除;对于选项D :因为()3xf x =,所以其定义域为R 关于原点对称,因为()()33xxf x f x --===,所以函数()3x f x =为R 上的偶函数,又当0x >时,()3x f x =,又因为指数函数3x y =为R 上的增函数,所以函数()3xf x =为()0,∞+上的增函数,故选项D 符合题意.故选:D【点睛】本题考查函数奇偶性的判断和幂函数、指数函数和对数函数的单调性;考查运算求解能力;熟练掌握基本初等函数的图象与性质是求解本题的关键;属于中档题.8.某几何体的三视图如图所示,则该几何体棱长的最大值为( )A. 5B. 6C.7 D.2【答案】C 【解析】【分析】如图所示:在长方体1111ABCD A B C D -中,N ABCD -满足三视图,计算棱长得到答案. 【详解】如图所示:在长方体1111ABCD A B C D -中,N ABCD -满足三视图. 则3ABCD ==,2AD BC ==,2NA ND ==,222117NB NC NA AA AB ==++=.故选:C .【点睛】本题考查了三视图,意在考查学生的计算能力和空间想象能力.9.惰性气体分子为单原子分子,在自由原子情形下,其电子电荷分布是球对称的.负电荷中心与原子核重合,但如两个原子接近,则彼此能因静电作用产生极化(正负电荷中心不重合),从而导致有相互作用力,这称为范德瓦尔斯相互作用.今有两个相同的惰性气体原子,它们的原子核固定,原子核正电荷的电荷量为q ,这两个相距为R的惰性气体原子组成体系的能量中有静电相互作用能221121111cU k q R R x x R x R x ⎛⎫=+-- ⎪+-+-⎝⎭,其中c k 为静电常量,1x ,2x 分别表示两个原子负电中心相对各自原子核的位移,且1x 和2x 都远小于R ,当x 远小于1时,()1211x x x -+≈-+,则U 的近似值为( )A. 21232c k q x x RB. 21232c k q x x R-C. 2123c k q x x RD. 2123c k q x x R-【答案】B 【解析】 【分析】把U 的表达式中的分子分母同时乘以R ,然后对括号中的每个分式的分子分母同时除以R ,结合题中的数据1x 和2x 都远小于R ,当x 远小于1时,()1211x x x -+≈-+,化简求解即可.【详解】根据题意,221121111cU k q R R x x R x R x ⎛⎫=+-- ⎪+-+-⎝⎭ 21212c k q R R R R R R R x x R x R x ⎛⎫=+-- ⎪+-+-⎝⎭212121111111c k q x x x x R R R R⎛⎫⎪=+--⎪- ⎪++-⎝⎭, 因为1x 和2x 都远小于R ,当x 远小于1时,()1211x x x -+≈-+,所以212121111111c k q x x x x R R R R⎛⎫ ⎪+-- ⎪- ⎪++-⎝⎭222212121122221111+c k q x x x x x x x x R R R R R R R ⎡⎤⎛⎫⎛⎫--⎛⎫≈+-+--+-+⎢⎥ ⎪ ⎪ ⎪⎝⎭⎢⎥⎝⎭⎝⎭⎣⎦()222212121122222c x x k q x x x x x x RR R R R R R ⎡⎤--≈-++---⎢⎥⎢⎥⎣⎦21232c k q x x R≈-, 故选:B【点睛】本题考查U 的近似计算;考查运算求解能力和逻辑推理能力;对U 的表达式进行适当的变形,充分运用题中的数据是求解本题的关键;属于中档题.10.设a =,2log 13b =, 1.52c =,则下列正确的是( ) A.c b a <<B. a c b <<C.c a b <<D.b c a <<【答案】C 【解析】 【分析】由题意知, 1.52c ==,利用幂函数y =a c >,构造函数()()2log 0f x x x =>,通过求导判断函数()f x 的单调性,利用函数()f x 判断,a b 的大小关系即可.【详解】由题意知, 1.52c ==y =[)0,+∞上单调递增,所以>a c >;令()()2log 0f x x x =>,则()122ln 22ln 2f x x x '==,所以()0f x '=时,22ln 2x ⎛⎫= ⎪⎝⎭,当220,ln 2x ⎛⎫⎛⎫∈ ⎪ ⎪ ⎪⎝⎭⎝⎭时,()0f x '>,当22,ln 2x ⎛⎫⎛⎫∈+∞ ⎪ ⎪ ⎪⎝⎭⎝⎭时,()0f x '<, 所以函数()f x 在220,ln 2⎛⎫⎛⎫ ⎪ ⎪ ⎪⎝⎭⎝⎭上单调递增,在22,ln 2⎛⎫⎛⎫+∞ ⎪ ⎪ ⎪⎝⎭⎝⎭上单调递减,因为23ln 2ln ln e =>=2ln 23>,229ln 2⎛⎫< ⎪⎝⎭, 所以()()21316log 160f f >==,即2log 13>b a >,综上可知,c a b <<. 故选:C【点睛】本题考查通过求导判断函数的单调性、利用函数的单调性比较大小;考查运算求解能力和函数与方程的思想;通过构造函数()()2log 0f x x x =>,利用函数的单调性比较,a b 的大小是求解本题的关键;属于难度较大型试题. 11.将函数()222cos 1f x x x =+-的图象向右平移02πϕϕ⎛⎫<<⎪⎝⎭个单位长度后得到函数()g x 的图象,若对于满足()()124f x g x -=的1x ,2x ,有12min 6x x π-=,则ϕ=( )A.6π B.4π C.3πD.512π 【答案】C 【解析】 【分析】()2sin 26f x x π⎛⎫=+ ⎪⎝⎭,()2sin 226g x x π⎛⎫=+- ⎪⎝⎭ϕ,故12min 226T x x ππϕϕ-=-=-=,解得答案.【详解】()222cos 12cos 22sin 26f x x x x x x π⎛⎫=+-=+=+ ⎪⎝⎭,()2sin 226g x x π⎛⎫=+- ⎪⎝⎭ϕ,()()124f x g x -=,则12min226T x x ππϕϕ-=-=-=,故3πϕ=.故选:C .【点睛】本题考查了三角函数平移,根据函数最值求参数,意在考查学生的计算能力和应用能力.12.已知函数()()22,032,0x x e x f x x x x ⎧+≤=⎨-+>⎩,()(),3,f x x mg x x x m ⎧≤=⎨-+>⎩,若()g x 恰好有3个零点,则m 的取值范围是( ) A. [)2,1- B. (]2,1- C.[)[)1,23,+∞UD.(][)1,23,+∞U【答案】C 【解析】 【分析】画出函数图像,如图所示,讨论3m ≥和3m <两种情况,判断分段函数的零点个数,计算得到答案. 【详解】当0x ≤时,()()2x f x x e =+,则()()'3x f x x e =+,函数在(),3-∞-上单调递减,在[]3,0-上单调递增,()313f e -=-,画出()f x 的图像,如图所示: 当3m ≥时,()()0g x f x ==在(],m -∞上有3个零点,()3g x x =-+在(),m +∞没有零点,满足; 当3m <时,()3gx x =-+在(),m +∞上有一个零点,故()()0g x f x ==在(],m -∞上有两个零点,故12m ≤<.综上所述:[)[)1,23,m ∈+∞U .故选:C .【点睛】本题考查了根据零点个数求参数,意在考查学生的计算能力,作图能力,分类讨论能力和综合应用能力.第Ⅱ卷(非选择题共90分)本卷包括必考题和选考题两部分.第13题~第21题为必考题,每个试题考生都必须作答.第22题~第23题为选考题,考生根据要求作答.二、填空题:本大题共4小题,每小题5分.13.在二项式62x x ⎛⎫+ ⎪⎝⎭的展开式中,常数项的数值为________. 【答案】60 【解析】 【分析】通过二项式展开式的通项,令x 的指数等于零,求得r 的值,从而求得常数项. 【详解】()363216622rrr r r r r T Cx C x x --+⎛⎫==⋅⋅ ⎪⎝⎭当3302r -=,即2r =时,常数项为226260C ⋅=,故填60. 【点睛】本小题主要考查二项式展开式的通项公式.需要将二项展开式公式化简后,再来求指定项的值.属于基础题.14.在ABCD Y 中,()0,2AD =uuu r ,()2,3AC =u u u r ,则AB BD ⋅=u u u r u u u r______.【答案】3- 【解析】 【分析】利用平面向量加减法的三角形法则和坐标表示求出,AB BD u u u r u u u r的坐标,再利用平面向量数量积的坐标表示即可求解.【详解】如图,在ABCD Y 中,AD BC =u u u r u u u r,由平面向量加法的三角形法则知,ACAB BC =+u u u ru u u r u u u r,即AB AC BC =-u u u r u u u r u u u r,所以()2,1AB =u u u r ,又BD AD AB =-u u u r u u u r u u u r ,()0,2AD =uuur ,所以()2,1BD =-u u u r , 由平面向量的数量积的坐标表示知,AB BD ⋅=u u u r u u u r()22113⨯-+⨯=-.故答案为:3-【点睛】本题平面向量加减法的三角形法则和坐标表示、平面向量数量积的坐标表示;考查运算求解能力;熟练掌握平面向量加减法的三角形法则和坐标表示是求解本题的关键;属于中档题.15.设ABC V 的角A ,B ,C 的对边分别为a ,b ,c ,已知ABC V 的面积为24sin bB,且()2cos cos 3A CB --=,则cos B =______. 【答案】16【解析】 【分析】根据面积公式和正弦定理得到1sin sin 2A C =,利用和差公式计算得到1cos cos 3A C =,再根据()cos cosB AC =-+展开得到答案.【详解】21sin 24sin b S ac B B ==,故222sin b ac B =,即1sin sin 2A C =.()()()2cos cos cos cos 2cos cos 3A C B A C A C A C --=-++==,故1cos cos 3A C =. 故()1cos cos sin sin cos cos 6B AC A C A C =-+=-=. 故答案为:16. 【点睛】本题考查了正弦定理,面积公式,三角恒等变换,意在考查学生的计算能力和综合应用能力. 16.已知椭圆C 的焦点为1F ,2F ,过点1F 的直线与椭圆C 交于A ,B 两点.若112AF F B =,2AB BF =,则椭圆C 的离心率为______.【答案】【解析】 【分析】根据题意作出图形,设1BF x =,则122,3AF x BF AB x ===,利用椭圆的定义求出2AF 的表达式,在2ABF V 中利用余弦定理求出cos 2ABF ∠,在12BF F △中,利用余弦定理求出12F F 的表达式,代入离心率公式求解即可.【详解】根据题意,作图如下:设1BF x =,则122,3AF x BF AB x ===,由椭圆的定义知,122AF AF a +=,12342BF BF x x x a +=+==,因为12AF x =,所以22AF x =,在2ABF V 中,由余弦定理可得,2222222cos 2AB BF AF ABF AB BF +-∠=⋅()()()22233272339x x x x x+-==⋅⋅,在12BF F △中,由余弦定理可得,22212121222cos F F BF BF BF BF ABF =+-⋅⋅∠,即()2221273239F F x x x x =+-⋅⋅⋅,解得1243F F x =,所以4324,2a x c x ==,所以椭圆离心率23332xc e ax ===故答案为:3【点睛】本题考查椭圆的定义和性质、椭圆中焦点三角形的性质和余弦定理;考查数形结合的思想和运算求解能力;熟练掌握椭圆的定义和性质、椭圆中焦点三角形的性质是求解本题的关键;属于中档题.三、解答题:第17~21题每题12分,解答应在答卷的相应各题中写出文字说明,说明过程或演算步骤. 17.已知数列{}n a 的前n 项和为n S ,且满足*21()n n a S n N -=∈. (Ⅰ)求数列{}n a 的通项公式;(Ⅱ)设()2log 1nn b S =+,求数列11n n b b +⎧⎫⎨⎬⎩⎭的前n 项和n T .【答案】(Ⅰ)12n n a -=(Ⅱ)1nnT n =+ 【解析】 【分析】(Ⅰ)由*21()n n a S n N -=∈,可得,2n ≥,1121n n a S ---=,两式相减得到12n n a a -=,利用等比数列通项公式求解即可;(Ⅱ)结合(Ⅰ)可求出n S 的表达式,进而可得n b 的通项公式,利用裂项相消法求和即可. 【详解】(Ⅰ)21n n a S -=,令1n =,解得11a =,2n ≥,1121n n a S ---=,两式相减,得12n n a a -=,所以数列{}n a 是以11a =为首项,2q =为公比的等比数列,所以数列{}n a 的通项公式为12n n a -=;(Ⅱ)由(Ⅰ)知,12n n a -=,21n n S a =-,所以21nn S =-,即()22log 1log 2nn n b S n =+==, ∴1111111111223(1)2231n T n n n n ⎛⎫⎛⎫⎛⎫=++⋅⋅⋅+=-+-+⋅⋅⋅+- ⎪ ⎪ ⎪⨯⨯++⎝⎭⎝⎭⎝⎭1111nn n =-=++. 【点睛】本题考查利用n a 与n S 的关系求数列的通项公式、等比数列通项公式和裂项相消法求和;考查运算求解能力;熟练掌握已知n a 与n S 的关系求数列通项的方法和裂项相消法求和是求解本题的关键;属于中档题. 18.如图,在直三棱柱111ABC A B C -中,90BAC ∠=︒,1AB AC AA ==,E ,F 分别是AC 和AB 上动点,且AE BF =.(1)求证:11B E C F ⊥;(2)若2AE EC =,求二面角1A EF A --的平面角的余弦值.【答案】(1)证明见解析(2)27【解析】 【分析】 (1)以点A 为原点,分别以AB ,AC ,1AA 所在直线为x 轴,y 轴,z 轴建立坐标系,设AE n =,110B E C F ⋅=u u u r u u u u r,得到证明.(2)平面AEF 的法向量()16,3,2n =u r ,平面EAF 的法向量()20,0,1n =u u r,计算夹角得到答案.【详解】(1)以点A 为原点,分别以AB ,AC ,1AA 所在直线为x 轴,y 轴,z 轴建立坐标系,不妨设3AB =,则()0,0,0A ,()3,0,0B ,()0,3,0C ,()10,0,3A ,()13,0,3B ,()10,3,3C .设AE n =,则()0,,0En ,()3,0,0F n -,∴()13,,3B E n =--u u u r ,()13,3,3C F n =---u u u u r,∵()()113,,33,3,30B E C F n n ⋅=--⋅---=u u u r u u u u r ,∴11B E C F ⊥u u u r u u u u r,即11B E C F ⊥.(2)由2AE EC =,得()0,2,0E,()1,0,0F ,∴()10,2,3A E =-u u u r ,()1,2,0EF =-u u u r ,()1,0,0AF =u u u r, 设平面AEF 的法向量()1,,n x y z =u r ,∵()10,2,3A E =-u u u r ,()1,2,0EF =-u u u r, 由11100n A E n EF ⎧⋅=⎪⎨⋅=⎪⎩u v u u u vu v u u u v ,得23020y z x y -=⎧⎨-=⎩,令3y =,得6x =,2z =,∴()16,3,2n =u r ,∵1A A ⊥平面EAF ,∴平面EAF 的法向量()20,0,1n =u u r,∴12122cos 7n n n n θ⋅==⋅u r u u r ur u u r ,所以二面角1A EF A --的余弦值为27.【点睛】本题考查了线线垂直,二面角,意在考查学生的计算能力和空间想象能力. 19.某流行病爆发期间,某市卫生防疫部门给出的治疗方案中推荐了三种治疗药物A ,B ,C (A ,B ,C 的使用是互斥且完备的),并且感染患者按规定都得到了药物治疗.患者在关于这三种药物的有关参数及市场调查数据如下表所示:(表中的数据都以一个疗程计)(1)从感染患者中任取一人,试求其一个疗程被治愈的概率大约是多少? (2)求感染患者在一个疗程的药物治疗费用的分布列及其数学期望. 【答案】(1)0.885(2)详见解析 【解析】 【分析】(1)直接利用概率定义公式计算得到答案.(2)X 的取值有600,1000,800,计算概率得到分布列,再计算数学期望得到答案.【详解】(1)30585%12295%18390%0.885305122183⨯+⨯+⨯=++;(2)感染者在一个疗程的药物治疗费是600元的概率为3050.5305122183=++,治疗费是1000元的概率为1220.2305122183=++;治疗费是800元的概率为1830.3305122183=++; 分布列为6000.510000.28000.3740EX =⨯+⨯+⨯=元.【点睛】本题考查了概率的计算,分布列,数学期望,意在考查学生的计算能力和应用能力. 20.已知M e :()22114x y -+=,直线l :12x =-,动圆P 与M e 相外切,且与直线l 相切.设动圆心P 的轨迹为C .(1)求曲线C 的方程; (2)过点()1,0D-的直线与曲线C 交于A ,B 两点(点A 在点D ,B 之间),点Q 满足3QA AM =u u u r u u u u r,求ABM V 与ADQ △的面积之和取得最小值时直线AB 的方程.【答案】(1)24y x =(2)y x =+y x =【解析】 【分析】(11x =+,化简得到答案.(2)设方程为y kx k =+,设()11,Ax y ,()22,B x y ,计算14Q y y =,联立方程得到124y y =,122ABM ADQ y S y S +=+△△,利用均值不等式计算得到答案.【详解】(1)设(),P x y 1x =+,化简后,得24y x =.(2)易知直线AB 的斜率存在,且不为零,其方程为y kx k =+,设()11,Ax y ,()22,B x y ,3QA AM =u u u r u u u u r,即()()1111,31,0Q Q x x y y x y -=---,∴14Q y y =,()11,A x y ,()22,B x y 满足24y kx k y x=+⎧⎨=⎩,消去x ,得2440ky y k -+=,124y y =,2ABM ADQ QDM BDM ADM S S S S S +=+-△△△△△211112222222Q y y y =⨯+⨯-⨯⨯ 21121-242Q y y y y y y =+=+-122y y =+≥==.当且仅当122142y y y y =⎧⎨=⎩,即12y y ⎧=⎪⎨=⎪⎩或12y y ⎧=⎪⎨=-⎪⎩ABM V 与ADQ △的面积之和最小,最小值为1y 时,211142y x ==,12A ⎛ ⎝,直线l的方程为y x =+;1y =时,211142y x ==,1,2A ⎛ ⎝,直线l的方程为33y x =--. ∴ABM V 与ADQ △的面积之和最小值直线l的方程为33y x =+或33y x =--. 【点睛】本题考查了轨迹方程,三角形面积的最值问题,意在考查学生的计算能力和综合应用能力. 21.已知()()2x f x xe ax a R =-+∈.(1)若曲线()y f x =在0x =处的切线与坐标轴围成的图形面积为4,求实数a 的值;(2)若1a ≤,求证()ln 3f x x ≥+.【答案】(1)12a =,或32a =(2)证明见解析 【解析】 【分析】(1)求导得到()'01f a =-,()02f =得到切线方程,241A S a ==-,解得答案. (2)ln 1ln 1x x x e ax x x e x x ⋅---≥⋅---,设()()ln 10x gx xe x x x =--->,求导得到()()1'1x g x x e x ⎛⎫=+- ⎪⎝⎭,设零点为0x ,则()()0min 0g x g x ==,得到证明.【详解】(1)由()()'1x f x x e a =+-,∴()'01f a =-,又()02f =,∴切线方程为()12y a x =-+,则241A S a ==-,解得12a =,或32a =;(2)由()ln 3ln 1x f x x xe ax x --=---,易知0x >,∴当1a ≤时,ln 1ln 1x x x e ax x x e x x ⋅---≥⋅---, 令()()ln 10x gx xe x x x =--->,则()()1'1xg x x e x ⎛⎫=+-⎪⎝⎭,设()'g x 的零点为0x , 则010x ex -=,即001x x e =且00ln x x =-,()g x 在()00,x 上递减,()0,x +∞上递增, ∴()()000min ln 0gx g x x x ==--=,∴0x >时,()0g x ≥恒成立,从而()ln 30f x x =-≥恒成立,∴1a ≤时,()ln 3f x x ≥+总成立.【点睛】本题考查了函数的切线问题,证明不等式,意在考查学生的计算能力和综合应用能力.选考题:共10分.请考生在第22,23题中任选一题作答,如果多做,则按所做的第一题计分.作答时用2B 铅笔在答题卡上把所选题目的题号涂黑.22.在平面直角坐标系xOy 中,将曲线C :221x y +=上的点按坐标变换'2'x xy y=⎧⎨=⎩,得到曲线'C ,M 为C 与x 轴负半轴的交点,经过点M 且倾斜角为60︒的直线l 与曲线C 的另一个交点为N ,与曲线'C 的交点分别为A ,B (点A 在第二象限).(Ⅰ)写出曲线'C 的普通方程及直线l 的参数方程; (Ⅱ)求AN BM -的值.【答案】(Ⅰ)2214xy +=,1122x t y ⎧=-+⎪⎪⎨⎪=⎪⎩(t 为参数);(Ⅱ)913- 【解析】 【分析】(Ⅰ)利用伸缩变换公式,把'2'x x y y ⎧=⎪⎨⎪=⎩代入C 的方程221x y +=,化简整理即可;由曲线C 的方程求出点M 的坐标,利用倾斜角求出其余弦值和正弦值,代入直线参数方程的标准形式即可求解;(Ⅱ)利用弦长公式求出MN ,联立直线的参数方程和曲线'C 的方程,利用直线参数方程中参数t 的几何意义求出,AM BM ,进而求出AN BM -的值.【详解】(Ⅰ)由题得'2'x x y y ⎧=⎪⎨⎪=⎩代入C 的方程221x y +=得'C :22''14x y +=,即'C 的方程为2214x y +=,因为曲线C :221x y +=,令0y =,则1x =±,因为M 为C 与x 轴负半轴的交点,所以点()1,0M-,因为直线l 的倾斜角为60︒,所以1cos 60,sin 6022==o o , 所以l的参数方程为1122x t y t ⎧=-+⎪⎪⎨⎪=⎪⎩(t 为参数);(Ⅱ)因为()1,0M-,所以直线l的方程为)1y x =+,因为圆C 的圆心为()0,0,半径为1,所以圆心C 到直线l 的距离为d ==,由弦长公式可得,1MN ===,将112x t y ⎧=-+⎪⎪⎨⎪=⎪⎩(t 为参数)代入2214x y +=,整理得2134120t t --=,设1t ,2t 为方程的两个根,则12413t t +=,121213t t ⋅=-, ∴1291113AN BM AM BM t t -=--=+-=-. 【点睛】本题考查伸缩变换公式和、直线参数方程的标准形式、利用直线参数t 的几何意义求弦长;考查运算求解能力;熟练掌握直线参数方程中参数的几何意义是求解本题的关键;属于中档题.23.已知函数()21f x x a x =+--,a R ∈.(Ⅰ)当1a =时,求不等式()0f x ≥的解集;(Ⅱ)设函数()4gx x =-+,若函数()f x 的图象与函数()g x 的图象只有一个公共点,求a 的取值范围.【答案】(Ⅰ)[]0,2;(Ⅱ)3a >或4a =-. 【解析】 【分析】(Ⅰ)()0f x ≥等价于121x x +≥-,不等式两边同时平方得到关于x 的一元二次不等式,利用一元二次不等式解法求解即可; (Ⅱ)把方程214x a x x +--=+只有一个实数根转化为函数y x a =+与214y x x =-++的图象只有一个交点,分别作出两个函数图象,利用数形结合的思想进行求解即可. 【详解】(Ⅰ)因为1a =,∴不等式()0f x ≥即为121x x +≥-,两边平方得2360x x -≤,解得02x ≤≤,即1a =时,()0f x ≥的解集为[]0,2;(Ⅱ)由题意知,方程214x a x x +--=+只有一个实根,即y x a =+与214y x x =-++的图象只有一个交点,因为153,221413,2x x y x x x x ⎧-≤⎪⎪=-++=⎨⎪+>⎪⎩,又y x a =+的图象由y x =向左()0a >或向右()0a <平移了a 个单位,作图如下:21由图象可知,它们只有一个公共点,则3a >或4a =-.【点睛】本题考查绝对值不等式的解法和利用数形结合思想解决函数交点问题;考查运算求解能力和数形结合思想;熟练掌握含有两个绝对值不等式的解法是求解本题的关键;属于中档题.。

新疆维吾尔自治区乌鲁木齐市2019届高三第二次诊断性测试语文试卷 Word版含解析

新疆维吾尔自治区乌鲁木齐市2019届高三第二次诊断性测试语文试卷 Word版含解析

2019年高三年级第二次诊断性测试语文试卷(卷面分值:150分;考试时间:150分钟)注意事项:1.本试卷为问答分离式试卷,由问卷和答题卡(答卷)两部分组成,答案务必写或涂在指定位置上。

2.答题前,请考生务必将自己的学校、姓名、准考证号、科别等信息填写在答题卡(答卷)的密封区内。

一、现代文阅读(36分)(一)论述类文本阅读(本题共3小题,9分)阅读下面的文字,完成各题。

庄子和尼采是处于不同历史时代的哲学家,虽然处于不同的历史背景之下,但相似的是,二人都对各自的文化传统进行了批判,并作出自己的价值重估,着重强调人的精神自由。

”庄子的哲学是批判宗法制礼教文化对人性的束缚,强调对人的精神自由的追求。

他认为“人为”和“自为”两种因素束缚着人,使人不得自由,他对儒家的“圣人”说,仁义礼智及当时的社会关系进行了猛烈的攻击。

尼采生活在19世纪的德国,基督教教义影响着人们的价值观念。

同时,资本主义开始发展,机器生产带来物质繁荣,人异化成机器的奴隶。

欧洲陷入了前所未有的信仰危机和价值危机。

尼采的哲学是建立在希腊悲剧精神的重建以及反基督教文化之上的。

他认为基督教是人追求精神自由的最大阻碍,因此他对基督教进行了批判,认为一切价值需重新评判,每个人都必须自己作人生的决定和命运的抉择。

庄子身处动荡变迁之时,战乱频繁,死亡时刻威胁人类。

人生是苦难的,生命如白驹过隙,短暂易逝,世人对死亡充满畏惧。

庄子为人们提供了一种在这样的生活环境中求得内心平静的方法,即站在道的角度看待生死,超越生与死的界限,视生死为大道的自然造化,顺其自然,将自身与道融为一体,从而达到心灵的宁静。

“死生,命也。

其有夜旦之常,天也。

人之有所不得与,皆物之情也。

”社会充满凶险,生命朝不保夕,如何才能在“方今之时,仅免于刑”的社会中保身呢?庄子告诉我们“直木先伐,甘井先竭”,有才能的人劳苦奔忙,结果往往“中于机辟,死于网罟”,所以只有像庖丁的解牛刀一样巧妙地避免与社会发生碰撞,才能够活得自由。

2019-2020学年乌鲁木齐市高级中学高三语文二模试卷及参考答案

2019-2020学年乌鲁木齐市高级中学高三语文二模试卷及参考答案

2019-2020学年乌鲁木齐市高级中学高三语文二模试卷及参考答案一、现代文阅读(36分)(一)现代文阅读I(9分)阅读下面的文字,完成下面小题。

美人鱼侯发山乌苏里江美其名曰江,其实是一条河,属于黑龙江的支流,是中俄边境上的界河。

那一年夏天,我去那里旅游。

之前,我还不止听一个人说过,乌苏里江有美人鱼。

美人鱼的古老传说,跨越了文化、地域和世纪,在世界范围内广泛传播。

美人鱼的故事不仅出现在安徒生的童话里,出现在博物学家普利尼的《自然史》中,还出现在现实当中,如当年哥伦布航海途中,就发现了美人鱼。

即便是在今天,在世界一些遥远的地区,还不时传来发现美人鱼的报道。

因此,我对乌苏里江里有美人鱼的传说倒有几分相信。

美人鱼什么模样?美人的上身,鱼的尾巴,这我知道。

具体到细节,如眼睛的大小,如头发的长短,如脸蛋的形状,我想象不出来。

我赶到的时候,天色已晚。

当晚借宿在江边的一个村子。

那户人家只有一位七十多岁的老大爷。

从跟老人的攀谈中,我知道老人这辈子没有子女,老伴五年前走了。

当下我心里咯噔一下,心说这样的孤寡老人怎么生活啊?我四下瞅瞅,发觉家里收拾得干净清爽,一点也不乱。

难道请保姆或钟点工?不像。

我说,大爷,您身体还行啊。

老了,啥也干不动喽。

老人摇了摇手。

我以为老人谦虚,说您还真行,家里拾掇得这么齐整。

老人笑了笑,说我哪行,都是美人鱼干的。

美人鱼?我吓了一跳,以为老人脑子不灵醒,说胡话哩,我也只好顺着他的话茬往下走,说美人鱼什么时间来?老人说,美人鱼天天来,这不,桶里的鱼就是她送来的。

你来之前她刚走。

顺着老人的眼光,我看到屋角有个水桶,里面扑腾着几条鱼。

我淡淡一笑,老人的一番话更像传说中狐仙变成美丽女孩的故事。

这下,我更加认为老人是真的糊涂了,糊涂得还不轻。

老人从水桶里抓出一条鱼,熟练地给解剖了,然后从鱼骨上剔下两整块,切成相互连接的鱼条,再将鱼肉从鱼皮上片下,切成鱼丝,拌上用开水烫过的土豆丝、绿豆芽、韭菜、辣椒油、醋、盐等。

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