本节课是正弦函数、余弦函数图像的继续,本课是正弦曲线、余弦曲线这两种曲线的特点得出正弦函数、余弦函数的性质. 课程目标1.了解周期函数与最小正周期的意义;2.了解三角函数的周期性和奇偶性;3.会利用周期性定义和诱导公式求简单三角函数的周期;4.借助图象直观理解正、余弦函数在[0,2π]上的性质(单调性、最值、图象与x轴的交点等);5.能利用性质解决一些简单问题. 数学学科素养1.数学抽象:理解周期函数、周期、最小正周期等的含义; 2.逻辑推理: 求正弦、余弦形函数的单调区间;3.数学运算:利用性质求周期、比较大小、最值、值域及判断奇偶性.4.数学建模:让学生借助数形结合的思想,通过图像探究正、余弦函数的性质.重点:通过正弦曲线、余弦曲线这两种曲线探究正弦函数、余弦函数的性质; 难点:应用正、余弦函数的性质来求含有cosx,sinx的函数的单调性、最值、值域及对称性.
指数函数与幂函数是相通的,本节在已经学习幂函数的基础上通过实例总结归纳指数函数的概念,通过函数的三个特征解决一些与函数概念有关的问题.课程目标1、通过实际问题了解指数函数的实际背景;2、理解指数函数的概念和意义.数学学科素养1.数学抽象:指数函数的概念;2.逻辑推理:用待定系数法求函数解析式及解析值;3.数学运算:利用指数函数的概念求参数;4.数学建模:通过由抽象到具体,由具体到一般的思想总结指数函数概念.重点:理解指数函数的概念和意义;难点:理解指数函数的概念.教学方法:以学生为主体,采用诱思探究式教学,精讲多练。教学工具:多媒体。一、 情景导入在本章的开头,问题(1)中时间 与GDP值中的 ,请问这两个函数有什么共同特征.要求:让学生自由发言,教师不做判断。而是引导学生进一步观察.研探.
二、典例解析例4. 用 10 000元购买某个理财产品一年.(1)若以月利率0.400%的复利计息,12个月能获得多少利息(精确到1元)?(2)若以季度复利计息,存4个季度,则当每季度利率为多少时,按季结算的利息不少于按月结算的利息(精确到10^(-5))?分析:复利是指把前一期的利息与本金之和算作本金,再计算下一期的利息.所以若原始本金为a元,每期的利率为r ,则从第一期开始,各期的本利和a , a(1+r),a(1+r)^2…构成等比数列.解:(1)设这笔钱存 n 个月以后的本利和组成一个数列{a_n },则{a_n }是等比数列,首项a_1=10^4 (1+0.400%),公比 q=1+0.400%,所以a_12=a_1 q^11 〖=10〗^4 (1+0.400%)^12≈10 490.7.所以,12个月后的利息为10 490.7-10^4≈491(元).解:(2)设季度利率为 r ,这笔钱存 n 个季度以后的本利和组成一个数列{b_n },则{b_n }也是一个等比数列,首项 b_1=10^4 (1+r),公比为1+r,于是 b_4=10^4 (1+r)^4.
二、典例解析例3.某公司购置了一台价值为220万元的设备,随着设备在使用过程中老化,其价值会逐年减少.经验表明,每经过一年其价值会减少d(d为正常数)万元.已知这台设备的使用年限为10年,超过10年 ,它的价值将低于购进价值的5%,设备将报废.请确定d的范围.分析:该设备使用n年后的价值构成数列{an},由题意可知,an=an-1-d (n≥2). 即:an-an-1=-d.所以{an}为公差为-d的等差数列.10年之内(含10年),该设备的价值不小于(220×5%=)11万元;10年后,该设备的价值需小于11万元.利用{an}的通项公式列不等式求解.解:设使用n年后,这台设备的价值为an万元,则可得数列{an}.由已知条件,得an=an-1-d(n≥2).所以数列{an}是一个公差为-d的等差数列.因为a1=220-d,所以an=220-d+(n-1)(-d)=220-nd. 由题意,得a10≥11,a11<11. 即:{█("220-10d≥11" @"220-11d<11" )┤解得19<d≤20.9所以,d的求值范围为19<d≤20.9
二、典例解析例10. 如图,正方形ABCD 的边长为5cm ,取正方形ABCD 各边的中点E,F,G,H, 作第2个正方形 EFGH,然后再取正方形EFGH各边的中点I,J,K,L,作第3个正方形IJKL ,依此方法一直继续下去. (1) 求从正方形ABCD 开始,连续10个正方形的面积之和;(2) 如果这个作图过程可以一直继续下去,那么所有这些正方形的面积之和将趋近于多少?分析:可以利用数列表示各正方形的面积,根据条件可知,这是一个等比数列。解:设正方形的面积为a_1,后续各正方形的面积依次为a_2, a_(3, ) 〖…,a〗_n,…,则a_1=25,由于第k+1个正方形的顶点分别是第k个正方形各边的中点,所以a_(k+1)=〖1/2 a〗_k,因此{a_n},是以25为首项,1/2为公比的等比数列.设{a_n}的前项和为S_n(1)S_10=(25×[1-(1/2)^10 ] )/("1 " -1/2)=50×[1-(1/2)^10 ]=25575/512所以,前10个正方形的面积之和为25575/512cm^2.(2)当无限增大时,无限趋近于所有正方形的面积和
课前小测1.思考辨析(1)若Sn为等差数列{an}的前n项和,则数列Snn也是等差数列.( )(2)若a1>0,d<0,则等差数列中所有正项之和最大.( )(3)在等差数列中,Sn是其前n项和,则有S2n-1=(2n-1)an.( )[答案] (1)√ (2)√ (3)√2.在项数为2n+1的等差数列中,所有奇数项的和为165,所有偶数项的和为150,则n等于( )A.9 B.10 C.11 D.12B [∵S奇S偶=n+1n,∴165150=n+1n.∴n=10.故选B项.]3.等差数列{an}中,S2=4,S4=9,则S6=________.15 [由S2,S4-S2,S6-S4成等差数列得2(S4-S2)=S2+(S6-S4)解得S6=15.]4.已知数列{an}的通项公式是an=2n-48,则Sn取得最小值时,n为________.23或24 [由an≤0即2n-48≤0得n≤24.∴所有负项的和最小,即n=23或24.]二、典例解析例8.某校新建一个报告厅,要求容纳800个座位,报告厅共有20排座位,从第2排起后一排都比前一排多两个座位. 问第1排应安排多少个座位?分析:将第1排到第20排的座位数依次排成一列,构成数列{an} ,设数列{an} 的前n项和为S_n。
由于三角函数是刻画周期变化现象的数学模型,这也是三角函数不同于其他类型函数的最重要的地方,而且对于周期函数,我们只要认识清楚它在一个周期的区间上的性质,那么它的性质也就完全清楚了,因此本节课利用单位圆中的三角函数的定义、三角函数值之间的内在联系性等来作图,从画出的图形中观察得出五个关键点,得到“五点法”画正弦函数、余弦函数的简图.课程目标1.掌握“五点法”画正弦曲线和余弦曲线的步骤和方法,能用“五点法”作出简单的正弦、余弦曲线.2.理解正弦曲线与余弦曲线之间的联系. 数学学科素养1.数学抽象:正弦曲线与余弦曲线的概念; 2.逻辑推理:正弦曲线与余弦曲线的联系; 3.直观想象:正弦函数余弦函数的图像; 4.数学运算:五点作图; 5.数学建模:通过正弦、余弦图象图像,解决不等式问题及零点问题,这正是数形结合思想方法的应用.
教学目标:1.引导幼儿参与学习活动,经历十几减几计算方法的探索与算理的建构过程。2.根据 11 至 20 各数的组成,掌握 20 以内不进位加法和不进位减法的计算方法。教学重点:十几减几(不退位)的计算。教学过程:一、复习导入复习10以内的数的组合,11~20各数的组成。1.碰球游戏导入,复习10的分解组合2.老师分别出示数字卡片:14、17、12、11。幼儿说数的组成。
(2)、中国坚持以互利合作实现共同繁荣----促进共同发展中国坚持以互利合作实现共同繁荣。中国连续担任经社理事会理事国,积极参与经社系统有关经济和社会发展的重要国际会议和其他活动并承办了联合国第四次世界妇女大会。中国积极推动南北对话和南南合作,敦促发达国家为实现全球普遍、协调、均衡发展承担更多责任。中国加人多项国际人权公约并认真履行公约义务,与联合国人权事务高级专员保持良好合作,与多国展开人权对话。相关链接:1995年9月,联合国第四次世界妇女大会在北京举行。来自197个国家和地区以及众多国际组织的1.76万名代表围绕会议主题“以行动谋求平等、发展与和平”展开热烈讨论。会议通过了《北京宣言》和《行动纲领》,为全球妇女事业的发展注入了新的活力。
1、三年的汗水,终于有了回报。站在领奖台上,她兴奋得不能自己,泪水刷刷地流了下来。误:不能自己 正:不能自已[bù néng zì yǐ] 2、灯光下面,人头攒动。这条街上陈列的,其实大都是膺品,但还是热闹非凡。误:膺品 正:赝品[yàn pǐn]3、待学生从农村基地回来时,校舍已修茸一新,三幢大楼披上了节日的盛装。误:修茸 正:修葺[xiū qì] 4、埋伏在左侧的三连,听到冲锋号响,尤如猛虎下山,直扑敌人阵地。误:尤如猛虎下山 正:犹如猛虎下山[yóu rú] 5、粗制滥造,哄抬市价,这种竭泽而鱼的做法,最后必然会让自己受到惩罚。误:竭泽而鱼 正:竭泽而渔[jié zé ér yú] 6、自从钢琴热掀起后,钢琴教师身价倍增,一批“三脚猫”也混迹其中,滥芋充数。误:滥芋充数 正:滥竽充数[làn yú chōng shù] 7、阳光穿射而入,配着店堂排列得整整齐齐的书架,真是一个书香花香阳光普照的世外桃园。误:世外桃园 正:世外桃源[shì wài táo yuán]8、在调查过程中,陈又将大批赃款转移至岳父处,专案组找他谈话时,他依旧装得若无其事。误:脏款 正:赃款[zāng kuǎn]
本节课是新版教材人教A版普通高中课程标准实验教科书数学必修1第四章第4.3.2节《对数的运算》。其核心是弄清楚对数的定义,掌握对数的运算性质,理解它的关键就是通过实例使学生认识对数式与指数式的关系,分析得出对数的概念及对数式与指数式的 互化,通过实例推导对数的运算性质。由于它还与后续很多内容,比如对数函数及其性质,这也是高考必考内容之一,所以在本学科有着很重要的地位。解决重点的关键是抓住对数的概念、并让学生掌握对数式与指数式的互化;通过实例推导对数的运算性质,让学生准确地运用对数运算性质进行运算,学会运用换底公式。培养学生数学运算、数学抽象、逻辑推理和数学建模的核心素养。1、理解对数的概念,能进行指数式与对数式的互化;2、了解常用对数与自然对数的意义,理解对数恒等式并能运用于有关对数计算。
本次活动由三个环节构成,即“动――静――动”,这拉,有利于突破重难点,我是这样掌开教学思路的。1、激发兴趣(第一环节)活动开始,教师扮演松鼠妈妈,幼儿扮小松鼠,在欢快的音乐声中,“妈妈”带着孩子们在草地上玩片刻后回到房子里休息,妈妈问:“孩子们,我们住的房子会动吗?你见过会动的房子吗?可是,有一只松鼠宝宝却建造了一座会动的房子,这到底是怎么一回事呢?”我以这样的形式导入,目的是激发幼儿兴趣,带着疑问听故事。2、组织教学,学习重点(第二环节)这一环节是让幼儿理解掌握故事内容,也是完成教学重点的主要环节,可分为三个小部分:(1)、视听结合,整体感知通过观看电脑课件,幼儿园完整欣赏故事,使他们对故事内容有初步整体的印象。设计提问:故事中有谁?会动的房子到底是怎么一回事?(2)、一问一 答,紧扣重点幼儿分片段观看,教师根据故事内容进行提问,启发引导,帮助幼儿具体感知,理解故事内容。设计提问:小松鼠在哪里造了房子?房子造好了发生了什么事?小松鼠分别到了哪些地方?那儿美吗?引导幼儿学习用语言进行表述,并模仿自然界美妙的声音:风声、海浪声、马儿奔跑声。
二、说活动家目标及重点难点1、理解故事情节,感受作品中清新的大自然画面。2、感受象声词,用语言正确地描述生活与自然的各种声音。3、丰富词汇,发展幼儿的观察力,思维能力和口语表达能力。本节课的重点是理解故事情节,难点是学习词语“手舞足蹈、惭愧、驮。”三、说活动准备1、课件制作2、场景布置:大树底下、山脚下、大海边、草原上。四、说教法:根据幼儿好奇、好问、好动、好模仿及具体形象思维占优势的特点,本次活动我主要采取以下几种教法。1、启发引导法:通过引导幼儿直观的观察,感知故事内容,并用递进式的提问,帮助幼儿理解故事。2、创设多媒体情景直观法:在活动中运用多媒体教学,符合幼儿爱看动画的特点。多媒体的声音,清晰美丽的画面,让孩子直接感知,从而更好的理解故事。五、说学法1、学观察:通过观看课件,把幼儿带入美丽、清新的大自然中,视觉与听觉的结合,使幼儿理解故事中的意境,感知自然界中的各种声响,调动幼儿的积极性,也激发了他们热爱大自然,热爱生活的情感。2、学思考:通过教师适当地提问,激发孩子们想象、思考、感受,发展幼儿的想象力。六、说活动过程:本次活动由三个环节构成,即“动――静――动”,这拉,有利于突破重难点,我是这样掌开教学思路的。1、激发兴趣(第一环节)活动开始,教师扮演松鼠妈妈,幼儿扮小松鼠,在欢快的音乐声中,“妈妈”带着孩子们在草地上玩片刻后回到房子里休息,妈妈问:“孩子们,我们住的房子会动吗?你见过会动的房子吗?可是,有一只松鼠宝宝却建造了一座会动的房子,这到底是怎么一回事呢?”我以这样的形式导入,目的是激发幼儿兴趣,带着疑问听故事。
活动目标:1、感受生活中有规律的序列,产生对规律活动的兴趣。2、能仔细观察、主动探索,感知规律的主要特征。3、尝试自创规律,发展幼儿的实际运用能力。活动准备:1、有色彩排列出规律的衣服。2、可以串挂的小积木若干,穿挂用的绳子人手一根。3、生活中有规律事物的课件(照片以幼儿身边场景为主)。
Her tutor told her to acknowledge __________ other people had said if she cited their ideas, and advised her _______(read) lots of information in order to form __________wise opinion of her own.Now halfway __________ her exchange year, Xie Lei felt much more at home in the UK. She said __________ (engage) in British culture had helped and that she had been__________ (involve) in social activities. She also said while learning about business, she was acting as a cultural messenger __________(build) a bridge between the two countries. keys:Xie Lei, a 19yearold Chinese student, said goodbye to her family and friends in China and boarded (board) a plane for London six months ago in order to get a business qualification. She was ambitious(ambition) to set up a business after graduation. It was the first time that she had left (leave) home.At first, Xie Lei had to adapt to life in a different country. She chose to live with a host family, who can help with her adaptation (adapt) to the new culture. When she missed home, she felt comforted (comfort) to have a second family. Also Xie Lei had to satisfy academic requirements. Her tutor told her to acknowledge what other people had said if she cited their ideas, and advised her to read lots of information in order to form a wise opinion of her own.Now halfway through her exchange year, Xie Lei felt much more at home in the UK. She said engaging (engage) in British culture had helped and that she had been involved (involve) in social activities. She also said while learning about business, she was acting as a cultural messenger building a bridge between the two countries.
? B: Absolutely! Getting involved with Chinese cultural activities there definitely helped a lot. I got to practice my Chinese on a daily basis, and I could learn how native Chinese speakers spoke.? A: What do you feel is your biggest achievement?? B: Learning Chinese characters! I have learnt about 1,500 so far. When I first started, I didn't think it was even going to be possible to learn so many, but now I find that I can read signs, menus, and even some easy newspaper articles.? A: What are you most keen on?? B: I've really become keen on learning more about the Chinese culture, in particular Chinese calligraphy. As I have learnt Chinese characters, I have developed a great appreciation for their meaning. I want to explore Chinese characters by learning how to write them in a more beautiful way. ? A: Finally, what do you want to say to anyone interested in learning Chinese?? I have really become keen on learning more about the Chinese culture, in particular Chinese Calligraphy. As I have learnt Chinese character, I have developed a great appreciation for their meaning. I want to explore Chinese characters by learning how to write them in a more beautiful way.? A: Finally, what do you want to say to anyone interested in learning Chinese?? B: I'd say, give it a shot! While some aspects may be difficult, it is quite rewarding and you will be happy that you tried.? A: Thanks for your time. ? B:You're welcome.
The activity theme of this section is to design various activities around the key words in the first text. Therefore, the activities require students to pay attention to the spelling of words. On the other hand, let students grasp the meaning of words more accurately through sentences and short texts. This kind of teaching design also helps to improve the ability of using English thinking.1. Cultivating students' ability to use word formation to induce and memorize vocabulary, and the ability to use lexical chunks to express meaning.2. Guide the students to think independently and use the correct form of words to complete sentences3. Cultivate students' habit of using lexical chunks to express language completely, guide students to draw words in sentences quickly, pay attention to word collocation, so as to accumulate more authentic expressions4. Instruct students to create sentences with the chunks.1. Enable students to use the language points in the real situation or specific contexts flexibly and appropriately.2. Guiding the Ss to use unit topic words and the sentence patterns in a richer context.Step1: Think of a word that best fits each definition.1. to remember sth2.to accept, admit, or recognize sth or the truth/existence of sth3. the process of changing sth or yourself to suit a new situation4 .to make sb feel less worried or unhappy5. a strong desire to achieve sth
The theme of this section is to express people's views on studying abroad. With the continuous development of Chinese economic construction, especially the general improvement of people's living standards, the number of Chinese students studying abroad at their own expense is on the rise. Many students and parents turn their attention to the world and regard studying abroad as an effective way to improve their quality, broaden their horizons and master the world's advanced scientific knowledge, which is very important for the fever of going abroad. Studying abroad is also an important decision made by a family for their children. Therefore, it is of great social significance to discuss this issue. The theme of this section is the column discussion in the newspaper: the advantages and disadvantages of studying abroad. The discourse is about two parents' contribution letters on this issue. They respectively express their own positions. One thinks that the disadvantages outweigh the advantages, and the other thinks that the advantages outweigh the disadvantages. The two parents' arguments are well founded and logical. It is worth noting that the two authors do not express their views on studying abroad from an individual point of view, but from a national or even global point of view. These two articles have the characteristics of both letters and argumentative essays1.Guide the students to read these two articles, and understand the author's point of view and argument ideas2.Help the students to summarize the structure and writing methods of argumentative writing, and guides students to correctly understand the advantages and disadvantages of studying abroad3.Cultivate students' ability to analyze problems objectively, comprehensively and deeply
《奇偶性》内容选自人教版A版第一册第三章第三节第二课时;函数奇偶性是研究函数的一个重要策略,因此奇偶性成为函数的重要性质之一,它的研究也为今后指对函数、幂函数、三角函数的性质等后续内容的深入起着铺垫的作用.课程目标1、理解函数的奇偶性及其几何意义;2、学会运用函数图象理解和研究函数的性质;3、学会判断函数的奇偶性.数学学科素养1.数学抽象:用数学语言表示函数奇偶性;2.逻辑推理:证明函数奇偶性;3.数学运算:运用函数奇偶性求参数;4.数据分析:利用图像求奇偶函数;5.数学建模:在具体问题情境中,运用数形结合思想,利用奇偶性解决实际问题。重点:函数奇偶性概念的形成和函数奇偶性的判断;难点:函数奇偶性概念的探究与理解.教学方法:以学生为主体,采用诱思探究式教学,精讲多练。
Activity 41. Students complete the task of activity 4, then teachers and students check the answers. 2. The teacher organized the students to work together and asked them to use the tables and mind maps sorted out before to retold the important choices in Lin Qiaozhi's life and their resultsStep 5 Language points1. The teacher asks the students to read the text carefully, find out the core words and long and difficult sentences in the text and draw lines, understand the use of vocabulary, and analyze the structure of long and difficult sentences. 2. The teacher explains and summarizes the usage of core vocabulary and asks the students to take notes. 3. The teacher analyzes and explains the long and difficult sentences that the students don't understand, so that the students can understand them better. Step 6 Homework1. Read the text again, in-depth understanding of the text; 2. Master the use of core vocabulary and understand the long and difficult sentences. 3. Complete relevant exercises in the guide plan. 1、通过本节内容学习,学生是否理解和掌握阅读文本中的新词汇的意义与用法;2、通过本节内容学习,学生能否结合文本特点总结林巧稚的人生原则和人格品质特征;3、通过本节内容学习,学生能否针对人生抉择发表自己的看法;能否全面地、客观地、理性地看待问题,进而对道德和人性有更加深入的思考和理解。
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