(A)⊥ αβ,且m?α(B)m∥n,且n⊥β(C)⊥ αβ,且m∥α(D)m⊥n,且n∥β (7)若m是2和8的等比中项,则圆锥曲线 2 21 y x m +=的离心率为 (A) 3 2 (B)5(C) 3 2 或 5 2 (D) 3 2 或5 (8)定义:()0 0> > =y, x y )y,x ( F x,已知数列{} n a满足: () ()n, F ,n F a n2 2 =() n* ∈N, 若对任意正整数n,都有 k n a a≥() k* ∈N成立,则 k a的值为 (A) 1 2 (B)2(C) 8 9 (D) 9 8 第Ⅱ卷(共110分) 二、填空题:本大题共6小题,每小题5分,共30分。 (9) 设a∈R,且2 (i)i a+为正实数,则a的值为 . (10) 若圆C的参数方程为 3cos1, 3sin x y =+ ? ? = ? θ θ( θ为参数),则圆C的圆心坐标为,圆C 与直线30 x y +-=的交点个数为 . (11)在平面直角坐标系xOy中,将点A(3,1)绕原点O逆时针旋转 90到点B,那么点B的坐标为____, 若直线OB的倾斜角为α,则sin2α的值为. (12) 如图,直线PC与O相切于点C,割线PAB经过圆心 O, 弦CD⊥AB于点E,4 PC=,8 PB=,则CE=. (13)已知函数 sin1 () 1 x x f x x -+ = + () x∈R的最大值为M,最小值为m,则M m +的值为__.
北京市东城区2015年中考二模英语试题及答案
北京市东城区2015年中考二模英语试题 知识运用(共25分)单项填空。(共10分,每小题1分) 21. — Do you know the foreign student in Class 2? —Yes. She's from America. ___ name is Alice. A. Her B. His C. My D. Its 22. —Dad, would you like to play chess with me? —Well, my dear, I'd love to, ___ I have to write a report. A. for B. and C. but D. or 23. The doctor told Mary that she ________ give up fatty foods because it was bad for her health. A. could B. should C. might D. would 24. —What a lovely dog! _____is it? —It's 11 years old. A. How much B. How heavy C. How long D. How old 25. While I ________ dinner last night, Angela called me and asked about homework. A. have B. will have C. was having D. am having 26. —Jim, do you want to come over for lunch tomorrow? —I'm sorry I can't. I _ a movie with some friends. A. am going to see B. see C. saw D. have seen 27. We can start the meeting now,as all the people ________. A. arrive B. have arrived C. arrived D. will arrive 28. Lily is a tidy girl. Her room ________ clean all the time A. kept B. was kept C. is kept D. keeps 29. My dad usually stops ________ a newspaper on his way home after work. A. to buy B. buying C. bought D. buy 30. —Tell me ________ my glasses, Sam. —They were just on the table, grandma. A. where will you find B. where you will find C. where did you find D. where you found 五. 完形填空 Last summer vacation, my brother got a set of bedroom furniture (家具) for his thirteenth birthday. When it arrived, I helped my parents moved the __31__ furniture to the garage(车库). It was still in good condition. I thought it might be a chance for us to __32__ someone in our community. I started to search neighbors, anyone who __33__ a bedroom set. Finally, my mom helped me call the local elementary school. They told me about Jaila, a second – grader, the daughter of a poor single mother. I was given an address and a telephone number, and I soon found my at Jaila’s. The moment I went into Jaila's room, I knew I had taken on too big a __34__. When I pushed the old door open,it made a long high noise. But the door was nothing compared with the rest of the room. Some old paint was 35 the wall. One of the windows was broken. The bed was just a mattress (床垫)lying on the old carpet (地毯).It seemed that the room needed more than furniture — it __36__ — for a complete makeover. That day I spent at least an hour looking around and wondering how I could possibly 37 the room. I had never painted a wall, let alone recarpeted a floor. The second day, I returned with a large group of 38 — my Girl Scout troop. We went to collect everything needed d oor to door in our community. We replaced, repainted, and redecorated Jaila's room. We sweated in Jaila’ s house for more than ten hours every day that week. The moment we finished, we called Juila into the room. She jumped, laughed and hugged each of us.
2018届北京市西城区高三理科数学二模试题及答案
2018届北京市西城区高三理科数学二模试题及答案
西城区高三模拟测试 数学(理科) 2018.5 第Ⅰ卷(选择题 共 40分) 一、 选择题:本大题共8小题,每小题5分,共40分.在每小题列出的四个选项中,选出 符合题目要求的一项. 1.若集合{|01}A x x =<<,2 {|20} B x x x =-<,则下列结论中 正确的是 (A )A B =? (B )A B =R (C )A B ? (D )B A ? 2.若复数z 满足(1i)1z -?=,则z = (A )1i 22+ (B )1i 22-+ (C )1i 22-- (D )1i 22- 3.下列函数中,既是偶函数又在区间(0,1)上单调递减的是 (A )1y x = (B )2 y x = (C )|| 2x y = (D )cos y x =
(A )②,③,①,④ (B )③,②,④,① (C )②,③,④,① (D )③,②,①,④ 第Ⅱ卷(非选择题 共110分) 二、填空题:本大题共6小题,每小题5分,共30分. 9.已知圆C 的参数方程为2cos , sin x y θθ =+?? =? (θ为参数),则圆C 的面积为____;圆心C 到直线 :340 l x y -=的距离为____. 10.2 4 1()x x +的展开式中2 x 的系数是____. 11.在△ABC 中,3a =,2b =,π3 A ∠=,则cos2 B =____.
12.设等差数列{}n a 的前n 项和为n S .若1 1a =,2 3 S S >,则 数列{}n a 的通项公式可以是____. 13.设不等式组 1, 3,25x x y x y ?? +??+? ≥≥≤ 表示的平面区域为D .若直 线0ax y -=上存在区域D 上的点,则 实数a 的取值范围是____. 14.地铁某换乘站设有编号为 A ,B ,C ,D ,E 的 五个安全出口.若同时开放其中的两个安全出口,疏散1000名乘客所需的时间如下: 安全出口编号 A ,B B ,C C ,D D ,E A , E 疏散乘客时间(s ) 120 220 160 140 200 则疏散乘客最快的一个安全出口的编号是____.
2020届东城区初三二模语文试卷(有答案)(已审阅)
北京市东城区第二学期高三综合练习(二) 语文 本试卷共10页,150分。考试时长150分钟。考生务必将答案答在答题卡上,在试卷上作答无效。考 试结束后,将本试卷和答题卡一并交回。 一、本大题共8小题,共24分。 阅读下面的文字,回答1—8题。 材料一 墨作为书写工具,同时也是重要的文化传承载体,已有几千年的历史。殷商时代的甲骨文就以石墨、朱砂填色。汉代纸料发明后,出现了一种以漆烟和松煤制成的丸状墨,这是日后用墨的滥觞.。 唐代是文化交流最广泛的朝代之一。唐末奚超避乱至歙州,见此地多松且质优,新安江水质极佳,因此留在此地制墨。因墨的主产区为歙州,故得名“歙墨”。其后奚超之子改进捣烟、和胶的方法,制成了“拈来轻、嗅来馨、磨来清”“丰肌腻理、光泽如漆”的佳墨。制墨工艺的改进,让书写更加流利,也加快了文化的传播速度。 宋室南渡后,宋墨的制作技艺臻.于成熟。制墨业的繁荣表现在三个方面:第一,油烟墨的创立,开辟了中国制墨业的新领域。千百年来,制墨主要以松烟为原料,由于长年累月取松烧烟,致使松树被砍伐殆.尽,新的制墨原料——桐油烟便应.运而生。第二,制墨从业人员众多,名家辈出。宋代制墨名家见诸史册的多达百余人,他们在选料、配方、烧制、用胶、捣杵等工艺方面,都有独到之处。第三,达官贵人及文人墨客与制墨工匠切磋技艺,促进了制墨技艺的发展。创造“瘦金体”书法的宋徽宗喜欢墨又懂制墨,他亲自实践,推动了制墨业的发展。苏轼、陆游、黄庭坚等文人都有过参与制墨的经历。宣和三年(1121),歙州改成徽州,“徽墨”之名正式诞生,并代代相传,延续至今。 明代徽墨进入了发展的黄金时期。先进的桐油烟与漆油的制墨方法被广泛应用。徽墨普遍加入麝香、冰片、熊胆等十几种贵重原料,使墨的质地达到新的水平。竞争使徽墨在工艺进步的同时也提升了造型设计能力和墨模的雕刻技术。徽墨呈现出艺术品的潜质,也带动了从事艺术的文化人士投身工艺品创作的潮流。清代徽墨的发展虽不及明代的规模,但陆续出现了曹素功、胡开文等制墨名家。这一时期徽墨出现了集锦种类的墨,墨雕题材也更加丰富。墨雕题材多取自山川、建筑、风光、典籍、典故、儒家、道家、佛家等,少则几锭为一套,多则几十锭为一套,徽墨成为多种文化元素的载体。 由于社会动荡,近代徽墨的发展一度停滞,直至解放后制墨业才重新焕发生机。随着国家对传统文化的重视与保护,徽墨被列入了首批国家级非物质文化遗产名录。承载着厚重历史和传统艺术文化的徽墨也注意吸收时代元素,不断开发新的产品。在快速发展的时代背景下,徽墨如同由传统文化之根生发的绿叶,它从传统文化中不断获得滋养,同时也以自身的发展扩充着中国文化的根系。 (取材于项颂的文章) 1.下列加点字的读音和解释,不正确 ...的一项是(2分) A.滥觞.:“觞”读作“shāng”意思是“酒杯” B.臻.于:“臻”读作“zhēn”意思是“达到(美好的境地)”
2019二模数学(理科带答案)
绝密★启用前 2019年普通高等学校招生全国统一考试 理科数学试题卷 ( 银川一中第二次模拟考试 ) 注意事项: 1.答卷前,考生务必将自己的姓名、准考证号填写在答题卡上。 2.作答时,务必将答案写在答题卡上。写在本试卷及草稿纸上无效。 3.考试结束后,将本试卷和答题卡一并交回。 一、选择题:本大题共12小题,每小题5分,满分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.如果复数 i ai +-21(R a ∈,i 为虚数单位)的实部与虚部相等,则a 的值为 A .1 B .-1 C .3 D .-3 2.若{}{} 0,1,2,|2,a A B x x a A ===∈,则A B =U A .{0,1,2} B. {0,1,23}, C. {0,1,24}, D. {1,24}, 3. 向量)3,1(),,2(-==b t a ρ,若b a ρ ,的夹角为钝角,则t 的范围是 A .t< 32 B .t>32 C .t<3 2 且t≠-6 D .t<-6 4.直线kx-2y+1=0与圆x 2 +(y-1)2 =1的位置关系是 A .相交 B .相切 C .相离 D .不确定 5.有6名男医生、5名女医生,从中选出2名男医生、1名女医生组成一个医疗小组, 则不同的选法共有 A .60种 B .70种 C .75种 D .150种 6.已知某个几何体的三视图如下,根据图中 标出的尺寸,可得这个几何体的表面积是 A .162+ B .122226+ C .1822+ D .1622+ 2 4 2 2
7. 下列函数中,最小正周期为π,且图象关于直线x=3 π 对称的函数是 A .y=2sin(2x+ 3π) B .y=2sin(2x-6π) C .y=2sin(32π+x ) D .y=2sin(2x-3 π ) 8.我国古代名著《庄子?天下篇》中有一句名言“一尺之棰, 日取其半,万世不竭”,其意思为:一尺的木棍,每天截 取一半,永远都截不完.现将该木棍依此规律截取,如图 所示的程序框图的功能就是计算截取20天后所剩木棍的 长度(单位:尺),则①②③处可分别填入的是 A .i i ,i S S ,i 21 20=-=< B .i i ,i S S ,i 21 20=-=≤ C .1220+== 时,不等式1221) ()(x x f x x f <恒成立,则实数a 的取值范围为 A .],(e -∞ B .),(e -∞ C .)2,(e -∞ D .]2 ,(e -∞ 二、填空题:本大题共4小题,每小题5分. 13.(x+y)(2x-y)5 的展开式中x 3y 3 的系数为_______. 14.在锐角三角形ABC 中,c b a ,,分别为角A 、B 、C 所对的边,且A c a sin 23= c=7,且ΔABC 的面积为 2 3 3,b a +的值为_______. 11 y x o 11 y x o 1 1 y x o 11 y x o
北京市东城区2016年中考二模英语试题word版含官方参考答案及评分标准
北京市东城区2015-2016学年第二学期初三统一练习(二) 英语2016.6 一、听对话,从下面各题所给的A、B、C三幅图片中选择与对话内容相符的图片。每 段对话你将听两遍。(共5分,每小题1分) 二、听对话或独白,根据对话或独白的内容,从下面各题所给的A、B、C三个选项中 选择最佳选项。每段对话或独白你将听两遍。(共15分,每小题1.5分) 请听一段对话,完成第6至第7小题。 6. What's the matter with the man? A. He has a fever. B. He has a cough. C. He has a headache. 7. When will the man go to see the doctor? A. Tomorrow morning. B. Tomorrow afternoon. C. Tomorrow evening. 请听一段刘话,完成第8至第9小题。 8. Where does the girl want to go? A. To a university. B. To a hospital. C. To a shopping center. 9. How long does it take to get there?
A. 10 minutes. B. 20 minutes. C. 30 minutes. 请听一段对话,完成第10至第11小题。 10. Why doesn't the woman want to watch a basketball game? A. Because she doesn't like basketball B. Because the ticket is very expensive. C. Because she watched one last weeekend 11. What do they decide to do at last? A. To go out for dinner. B. To watch a movie. C. To go to a concert. 请听一段对话,完成第12至第13小题。 12. What do we know about Pedro? A. His English is improving. B. He hates doing his homework. C. His English is better than his mother's. 13. What does the teacher tell Pedro's mother to do at home? A. To speak English with Pedro. B. To help Pedro with his listening. C. To make sure Pedro reads his book. 请听一段独白,完成第14至第巧小题。 14. Where is the speaker at the moment? A. In a shop. B. On a bus. C. On a river. 15. What's the speaker mainly doing? A. Telling about the tour plan. B. Giving advice on what to do. C. Describing some famous places. 三、听独白,记录关键信息。本段对话你将听两遍。(共10分,每小题2分) 请根据所听到的对话内容和提示词语,将所缺的关键信息填写在答题卡的相应位置上。 知识运用(共25分) 四、单项填空(共10分,每小题1分) 从下面各题所给的A、B、C、D四个选项中,选择可以填入空白处的最佳选项。21.These students always do homework very carefully. A. our B. his C. their D. her 22. Many people like to take a long vacation summer.
2019东城二模数学理科
高三数学(理)(东城) 第 1 页(共 11 页) 北京市东城区2018-2019学年度第二学期高三综合练习(二) 2019.5 数学 (理科) 本试卷共4页,共150分。考试时长120分钟。考生务必将答案答在答题卡上,在试卷上作答无效。考试结束后,将答题卡交回。 第一部分(选择题 共40分) 一、选择题共8小题,每小题5分,共40分。在每小题列出的四个选项中,选出符合题目要求的一项。 (1)已知集合2{2,1,0,1,2},{20}A B x x x =--=--≤,则A B =R e (A){2}- (B) {01}, (C) {2,1,2}-- (D) {1,0,1,2}- (2)执行如图所示的程序框图,输入2,5a b ==,那么输出的,a b 的值分别为 (A )7,3- (B )3-,3- (C )5,3- (D )5, 2 (3)已知向量a 与b 不共线,且AB m =+a b (1)m ≠,.AC n =+a b 若,,A B C 三点共 线,则实数,m n 满足的条件为 (A)1m n += (B) 1m n +=- (C) 1mn = (D)1mn =- (4)鲁班锁起源于中国古代建筑中首创的榫卯结构,相传由春 秋时代鲁国工匠鲁班所作. 右图是某个经典的六柱鲁班锁 及其六个构件的图片,下图是其中一个构件的三视图(单位:mm ), 则此构件的体积为 (A )334000mm (B ) 333000mm (C ) 332000mm (D )3 30000mm
高三数学(理)(东城) 第 2 页(共 11 页) (5)已知n S 是等差数列{}n a 的前n 项和,则“n n S na >对2n ≥恒成立”是“34a a >”的 (A) 充分而不必要条件 (B) 必要而不充分条件 (C) 充分必要条件 (D)既不充分也不必要条件 (6)教室的图书角摆放了一些阅读书目,其中有3本相同的论语、6本互不相同的近代文学名著,现从这9本书中 选出3本,则不同的选法种数为 (A) 84 (B) 42 (C) 41 (D)35 (7)已知正方体1111ABCD A B C D -的棱长为2,P 是底面ABCD 上的动点,1PA PC ≥,则满足条件的点P 构 成的图形的面积等于 (A) 12 (B) 4π (C) 44 π - (D) 72 (8)在交通工程学中,常作如下定义: 交通流量Q (辆/小时):单位时间内通过某一道路横断面的车辆数; 车流速度V (千米/小时):单位时间内车流平均行驶的距离; 车流密度K (辆/千米):单位长度道路上某一瞬间所存在的车辆数. 一般的, V 和K 满足一个线性关系:00 =(1)K V v k - (其中00,v k 是正数),则以下说法正确的是 (A) 随着车流密度的增大,车流速度在逐渐增大 (B) 随着车流密度的增大,交通流量在逐渐增大 (C) 随着车流速度的增大,交通流量先减小、后增大 (D) 随着车流速度的增大,交通流量先增大、后减小 第二部分(非选择题 共110分) 二、填空题共6小题,每小题5分,共30分。 ( 9 )已知复数1i 2i z -= 在复平面内对应的点为Z ,则Z 关于虚轴对称的点位于第 象限. ( 10 )已知2log 6a =,5log 15b =,若3log a m b >>,m * ∈N ,则满足条件的m 可以为_____. ( 11)椭圆22 124:1x y C b +=与曲线2C 关于直线y x =-对称,1C 与2C 分别在第一、二、三、四象限交于点1234,,,. P P P P 若四边形1234PP P P 的面积为4,则点1P 的坐标为_______, 1 C 的离心率为__ .
北京东城区中考数学二模试题及答案
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8.用min{a ,b }表示a ,b 两数中的最小数,若函数}1,1m in{2 2x x y -+=,则y 的图象为 二、填空题(本题共16分,每小题4分) 9. 反比例函数k y x = 的图象经过点(-2,1),则k 的值为_______. 10. 已知一个几何体的三视图如图所示,则该几何体是 . 主视图 俯视图11. 如图,将三角板的直角顶点放置在直线AB 上的点O 处.使斜边 CD ∥AB ,则∠a 的余弦值为__________. 12. 如图,Rt ABC △中,90ACB ∠=o ,30CAB ∠=o ,2BC =, O H ,分别为边AB AC ,的中点,将ABC △绕点B 顺时针旋 转120o 到11A BC △的位置,则整个旋转过程中线段OH 所扫过 部分的面积(即阴影部分面积)为 . 三、解答题(本题共30分,每小题5分) 13. 先化简,再求值:2 (21)(2)(2)4(1)x x x x x +++--+,其中33 x = . 14. 解分式方程: 1132 2x x x -+ =--. 15.如图,点A 、B 、C 的坐标分别为(3,3)、(2,1)、(5,1),将△ABC 先向下平移4 个单位,得△A 1B 1C 1;再将△A 1B 1C 1沿y 轴翻折,得△A 2B 2C 2. (1)画出△A 1B 1C 1和△A 2B 2C 2; (2)求线段B 2C 长. A H B O C 1O 1H 1A 1C y O A B C x y A 1-1-1-1-1 111 1 111 x y 0B x y C x y D
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