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人教版高中数学选择性必修二等差数列的前n项和公式（1）教学设计
高斯（Gauss，1777－1855），德国数学家，近代数学的奠基者之一. 他在天文学、大地测量学、磁学、光学等领域都做出过杰出贡献. 问题1：为什么1＋100＝2＋99＝…＝50＋51呢？这是巧合吗？试从数列角度给出解释.高斯的算法：（1+100）+（2+99）+…+(50+51)= 101×50=5050高斯的算法实际上解决了求等差数列：1，2，3，…，n，"… " 前100项的和问题.等差数列中，下标和相等的两项和相等.设 an＝n，则 a1＝1，a2＝2，a3＝3，…如果数列{an} 是等差数列，p，q，s，t∈N*，且 p＋q＝s＋t，则 ap＋aq＝as＋at 可得：a_1+a_100=a_2+a_99=?=a_50+a_51问题2： 你能用上述方法计算1＋2＋3＋… ＋101吗？问题3： 你能计算1＋2＋3＋… ＋n吗？需要对项数的奇偶进行分类讨论.当n为偶数时， S_n=(1+n)+[(2+(n-1)]+?+[(n/2+(n/2-1)]=(1+n)+(1+n)…+(1+n)=n/2 (1+n) =(n(1+n))/2当n为奇数数时， n－1为偶数
人教版高中数学选择性必修二等差数列的概念（1）教学设计
我们知道数列是一种特殊的函数，在函数的研究中，我们在理解了函数的一般概念，了解了函数变化规律的研究内容（如单调性，奇偶性等）后，通过研究基本初等函数不仅加深了对函数的理解，而且掌握了幂函数，指数函数，对数函数，三角函数等非常有用的函数模型。类似地，在了解了数列的一般概念后，我们要研究一些具有特殊变化规律的数列，建立它们的通项公式和前n项和公式，并应用它们解决实际问题和数学问题，从中感受数学模型的现实意义与应用，下面，我们从一类取值规律比较简单的数列入手。新知探究1.北京天坛圜丘坛，的地面有十板布置，最中间是圆形的天心石，围绕天心石的是9圈扇环形的石板，从内到外各圈的示板数依次为9,18,27,36,45,54,63,72,81 ①2.S，M，L，XL，XXL，XXXL型号的女装上对应的尺码分别是38,40,42,44,46,48 ②3.测量某地垂直地面方向上海拔500米以下的大气温度，得到从距离地面20米起每升高100米处的大气温度（单位℃）依次为25,24,23,22,21 ③
人教版高中数学选择性必修二等差数列的概念（2）教学设计
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
人教版高中数学选择性必修二等差数列的前n项和公式（2）教学设计
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。
人教版高中语文必修2《我有一个梦想》教案2篇
全班齐读第五段内容。请一位同学分析，接着让这位同学按他分析的读一遍。3、4两自然段的平缓之后，第5段作者的情感再次抬升。为了满足这种情感的张扬，作一口气连用了四个排比句式“现在是……时候”，一方面这是情感发泄的需要，另一方面这种排山倒海的语势也加强了内容的表达，极强地突出了现实为自由、平等而战的重要性。四、学会演讲我们刚才细读了课文，但读和讲是有区别的。所谓演讲，是一门语言艺术，它的主要形式是“讲”，即运用有声语言并追求言辞的表现力和声音的感染力；同时还要辅之以“演”，即运用面部表情、手势动作、身体姿态乃至一切可以理解的态势语言，使讲话“艺术化”起来，从而产生一种非凡的艺术魅力。那么，接下来就假设一下假如你是马丁·路德·金，你会怎样去讲这篇演讲辞。
人教版高中历史必修1祖国统一大业教案2篇
教材分析改革开放后我国的综合国力不断增强，人民对祖国统一的愿望越来越迫切。本节课以“一国两制”构想的提出，香港、澳门的回归和海峡两岸关系的发展为中心，说明实现祖国统一，完成中华民族复兴是历史发展的必然。第一目“‘一国两制’构想的提出”主要讲述了“一国两制”的含义及历史意义。第二目“香港、澳门的回归”着重讲述了香港回归、澳门回归的经过及历史意义，这是“一国两制”成功的实践。第三目“海峡两岸关系的发展”讲述了大陆注重发展与台湾的关系，促进海峡两岸的经济文化交流与合作，打破了几十年来海峡两岸的隔绝状态，促进了祖国统一的进程。此外，教材还通过“资料回放”“历史纵横”“学思之窗”等栏目，为学生学习提供了一些详细的史料。在教学中要分析图表资料，引导学生理解完成祖国统一大业，实现中华民族的复兴，是任何人也阻挡不了的历史潮流。
新人教版高中英语必修2Unit 1 Cultural Heritage-Reading and Thinking教案一
The theme of the reading and thinking is about “Understanding how a problem was solved”.The Listening & Speaking & Talking is about international co-work to protect the Mount Tai, in which the students from seven countries came up with many solutions even create the Mount Tai App. This section aims at showing how to solve a difficult and even tough problem about protecting the cultural heritage by the international co-work. So in this section, cultivating students’ international awareness is very clear and important. Concretely, with the economic development, how to balance the protection of cultural relics and social development is a big challenge for human. In the 1950s, the Egyptian government wanted to build the Aswan Dam across the Nile to control floods, produce electricity and water farms. But the proposal led to protests because it would destroy a lot of cultural relics. The Egyptian had no choice but ask the UN for help. Therefore, a international cooperation about how to protect the cultural relics began, which involved the time length about 20 years and a large amount of fund. Then, the problems was solved. 1. Read quickly to get the main idea and the structure of the article; read careful to get detailed information.2. Learn to use the reading strategy---making a timeline3. Learn how to solve a tough problem by asking for help and cooperation4. Have the international awareness and understand the great strength of international cooperation.1. Read quickly to get the main idea and the structure of the article; read careful to get detailed information.2. Learn to use the reading strategy---making a timeline.3. Learn how to solve a tough problem by asking for help and cooperation.
新人教版高中英语必修2Unit 2 Wildlife Protection-Discovering Useful Structure教案一
The activity topic of this section is "report an ongoing event", and the structure is the passive voice of present continuous tense. Rare wild animals are suffering from large-scale poaching, and species are on the brink of danger. Rescue operations are underway. "Being" and "suffering" are the meanings of the present progressive passive voice.The usage of present progressive passive voice is of great importance in writing a good discourse and appreciating some difficult language items, so it is vital to master it and use it flexibly in a context.1. Motivate Ss to deepen the understanding of the usage of present progressive passive voice in a fixed context.2. Enable Ss to master the usage of present progressive passive voice and use it flexibly in a context.3. Lead Ss to construct sentences or appreciate sentences used master it and use it flexibly in a context.1. Help students to appreciate the function of the usage of present progressive passive voice in a sentence2. Instruct students to write essays using the proper usage of present progressive passive voice.Look at the picture and tell me what are workers doing? What is the house being done?
新人教版高中英语必修2Unit 2 Wildlife Protection-Reading For Writing教案一
1. 标题首先根据海报的特点、格式写明标题。海报中往往把内容作为大标题。例如: Save the earth, Save the birds。2. 正文部分不同的海报其正文部分的侧重点不同。对于介绍性的海报, 首先要引出话题, 其次列出原因, 最后是总结。对于宣传类的海报, 要写明具体内容, 如: 活动内容, 地点以及参加活动的注意事项, 主持或举办单位等。1. 图片: 要选择引人注目的图片, 与主题要相关, 色彩明亮。话题句式 1. It is a treasure of our country. 它是我国的国宝。2. Believe it or not, at present only several thousand pandas exist in the world. 信不信由你, 目前世界上仅现存几千只熊猫。 3.It’s because of human activities that tigers are endangered. 正是因为人类的活动, 老虎处于濒危的状态。4. Many wild animals are in danger of dying out. 很多野生动物面临着灭绝的危险。 5. The government has taken effective measures to protect them. 政府已采取有效的措施来保护它们。6. People should raise the awareness of the protection of wild animals. 人们应该提高保护野生动物的意识。 7. It’s amazing that there are merely less than 1, 000 finless porpoises living in China. 非常令人吃惊, 目前中国仅有不足1 000只江豚。
新人教版高中英语必修2Unit 3 The Internet-Discovering Useful Structure教案一
This unit is about the Internet, which has a great influence to our humans and our lives. During the Listening & Speaking & Talking and Reading and Thinking section, the influence in examples has been shown. Thus, use the Present Perfect Tense is appropriate. However, in order to show the justice or weaken the doer of the behavior/action, it’s better to use the Present Perfect Passive Voice than the Present Perfect Tense. Besides, having learned to use the Present Perfect Passive Voice, students can beautify their language in their writing. 1. Learn the structure of the Present Perfect Passive Voice and its functions. 2. Learn to change the sentences with the Present Perfect Passive Voice into the sentences with the Present Perfect Passive Voice. 3. Learn to write sentences with the Present Perfect Passive Voice flexibly according to the context. 1. Learn the structure of the Present Perfect Passive Voice and its functions. 2. Learn to change the sentences with the Present Perfect Passive Voice into the sentences with the Present Perfect Passive Voice. 3. Learn to write sentences with the Present Perfect Passive Voice flexibly according to the context. Step 1 Observe the following sentences, then change the sentences into passive voice.He has been selected to take part in the sports meeting．(肯定句)他已被挑选出来参加运动会。The ink has not been removed from his overcoat．(否定句)墨迹还没有从他外套上去掉。
新人教版高中英语必修2Unit 5 Music-Discovering Useful Structures教案一
Step1:自主探究。1．(教材P52)Born(bear) in the USA on 2 January 1970, Whitacre began studying music at the University of Nevada in 1988．2．(教材P52) Moved(move) by this music, he said, “It was like seeing color for the first time．”3．(教材P56)I was very afraid and I felt so alone and discouraged(discourage)．4．(教材P58)Encouraged(encourage) by this first performance and the positive reaction of the audience, I have continued to play the piano and enjoy it more every day．Step2:语法要点精析。用法1：过去分词作表语1）．过去分词可放在连系动词be, get, feel, remain, seem, look, become等之后作表语，表示主语所处的状态Tom was astonished to see a snake moving across the floor．汤姆很惊讶地看到一条蛇正爬过地板。Finally the baby felt tired of playing with those toys．终于婴儿厌倦了玩那些玩具。注意：1）.过去分词作表语时与被动语态的区别过去分词作表语时，强调主语所处的状态；而动词的被动语态表示主语是动作的承受者，强调动作。The library is now closed．(状态)图书馆现在关闭了。The cup was broken by my little sister yesterday．(动作)昨天我妹妹把杯子打碎了。2）感觉类及物动词的现在分词与过去分词作表语的区别过去分词作表语多表示人自身的感受或事物自身的状态，常译作“感到……的”；现在分词多表示事物具有的特性，常译作“令人……的”。
新人教版高中英语必修2Unit 5 Music-Reading For Writing教案一
(4)Now we have heard a number of outstanding speeches ... 我们已经聆听了许多精彩的发言……(5)Because we wanted the nations of the world, working together, to deal with ... 因为我们希望全世界各国团结起来去应对……(6)And if we do not act ... 如果我们不采取行动……(7)Now, I share the concerns that have been expressed ... 我也同意对于……表达的担心(8)Let us show the world that by working together we can ... 让我们告诉全世界，通过一起努力我们可以……(9)It is now time for us to ... 是时候我们……(10)And I have always wished that ... 我一直希望……(11)Thank you for letting me share this day with me.感谢你们和我共度这一天。实践演练：假如你是高中生李华，你校将举办一次以“音乐”为主题的演讲比赛，请你按照主题，写下你的演讲稿。注意：词数100左右。First of all, thank you for listening to my speech. My topic is: love music like love yourself.Music is like the air we need to maintain our normal lives around us. You can't imagine how terrible a world without music would be. Movies and TV shows have no music, only dry conversations and scenes; mobile phones only vibrations; streets only noisy crowds; cafes, western restaurants only depressed meals. What a terrible world it is!As a student, I hope we all can enjoy the fun brought by music in our spare time. Instead of just listening to music, we can even make our own music. Let's enjoy the fun of music!Thanks again for your attention!
新人教版高中英语必修2Unit 1 Cultural Heritage-Discovering Useful Structure教案一
This teaching period mainly deals with grammar “restrictive relative clauses.” To begin with, teachers should lead students to revise what they have learned about the relative pronouns and relative adverbs. And then, teachers move on to stress more special cases concerning this grammar, such as the “preposition+ relative pronouns which and whom” and cases where we can omit the relative pronouns. This period carries considerable significance to the cultivation of students’ writing competence and lays a solid foundation for the basic appreciation of language beauty. The teacher is expected to enable students to master this period thoroughly and consolidate the knowledge by doing some exercises. 1. Guide students to review the basic usages of relative pronouns and adverbs of attributive clauses.2. Lead students to learn to use some special cases concerning restrictive relative clauses flexibly.2. Enable students to use the basic phrases structures flexibly.3. Strengthen students’ great interest in grammar learning.1. Help students to appreciate the function of relative pronouns and adverbs of attributive clauses in a sentence2. Instruct students to write essays using the proper relative pronouns and adverbs of attributive clauses.本节语法思考：定语从句在复合句中的作用是什么？ 关系词有哪些？定语从句在复合句中的作用相当于形容词，它在句中作定语修饰名词或代词。他们在先行词和定语从句之间起到联系作用，同时在意义上代表先行词并在定语从句中担任一个成分。被定语从句所修饰的词称先行词，定语从句一般放在先行词的后面。
新人教版高中英语必修2Unit 2 Wildlife Protection-Reading and Thinking教案一
The listening and speaking part aims at how to protect and help endangered animals by listening, speaking and talking about the facts and reasons. This lesson analyzes the decreasing clause of Tibetan antelope population and the measures of protecting Tibetan antelopes. So students can be guided to learn to analyse the title and use different reading skills or strategies, like scanning, skimming and careful reading.1. Read quickly to get the main ideas and the purpose of going to Tibetan; read carefully to understand what the author see and think.2. Understand the sentences of the present continuous passive voice such as “Much is being done to protect wildlife.” and the inverted sentence “Only when we learn to exist in harmony with nature can we stop being a threat to wildlife and to our planet.”3. Enhance the awareness of protecting wildlife.4. Cultivate the reading methods according to different materials.1. Read quickly to get the main ideas and the purpose of going to Tibetan; read carefully to understand what the author see and think.2. Understand the sentences of the present continuous passive voice such as “Much is being done to protect wildlife.” and the inverted sentence “Only when we learn to exist in harmony with nature can we stop being a threat to wildlife and to our planet.”3. Cultivate the reading methods according to different materials.Step 1 Leading-inWatch a video about elephants and whales and then ask:Why are they endangered ? They are killed/hunted
新人教版高中英语必修2Unit 3 The Internet-Listening &Speaking＆Talking教案一
Listening and Speaking introduces the topic of “ask about online habits”. Many middle school students have been surfing the Internet for many years, but what they do with the Internet and how much time they spend every day may not be very clear to themselves, nor to other students. This section allows students to investigate their peers' Internet use, which is conducive to their mutual understanding and understanding of the Internet. It can also help them reflect on their own online behavior, learn from other people's good online habits, and get rid of their bad online behavior.The listening text of this section is an investigation interview. The investigators interview specific groups with the same questions to obtain information, so as to understand their views, practices or attitudes on this issue. There are two specific questions: “how much time do you spend online every day? What do you usually do online?”. The answers of the three respondents provide rich and different information, and achieve the purpose of the investigators. The oral discourse structure of survey interviews generally includes greeting and explaining the purpose of the interview, presenting the interview questions and the respondents' answers. Listening and Talking introduces the theme of “choosing the right application ". Listening text is a conversation between Laura and Xiao Bo. In this part of listening, “oink”； “piggy bank” may cause the students' hearing comprehension limitation. Oink refers to sound word and pig's sound. So, add some oink to my piggy bank is often used to describe "making a little money".1. Guide students to understand the content of listening texts in terms of listening for definitions.2. Cultivate students' ability to define words and understand an investigation interview.
新人教版高中英语必修2Unit 3 The Internet-Reading and Thinking教案一
Paragraph 3. Jan decided to start an IT club to teach old people how to use computers and the Internet. Paragraph 4. Jan has started taking online classes to learn more about how to use the Internet to make society better. Paragraph 5. Jan’s life has been greatly improved by the Internet. Step 5: Critical thinking:(1)How do you arrange your time spent on study and the Internet? Is it reasonable? I usually surf the Internet using my mobile phone for only an hour after class, and it is reasonable for me.(2)What are your online activities? Are they safe? I chat with my friends, read news and play games. I never give away my private information so I think they are safe.Step 4: summary Much has been written about the wonders of the World Wide Web. There are countless articles (1)______(tell) us how the Internet has made our lives more convenient. But the Internet has done a lot (2)_____(much) for people than simply make life more convenient. People’s lives (3) _________________(change) by online communities and social networks so far. Take Jan for example, who developed a serious illness that made her (4)_____(stick) at home with only her computer to keep (5)___(she) company. She joined an online group (6)______ she could share problems, support and advice with others. She considered the ability to remove the distance between people as one of the greatest (7)_______(benefit). She was so inspired (8)____ she started an IT club in which many people have been helped. She has started to learn more about how to use the Internet to make society better. Her next goal is to start a charity website to raise money (9)___ children in poor countries. Jan’s life has been (10)______(great) improved by the Internet. Step 5 Homework:Review what we have learned and find out the key language points in the text.
新人教版高中英语必修2Unit 3 The Internet-Reading For Writing教案一
⑦identity theft 身份盗窃⑧chat room 聊天室⑨draft your blog post 起草博客帖子⑩post embarrassing photos 张贴尴尬照片 【话题句式】 1. How do you stay safe online and avoid bad experiences on the Internet? 你如何在网上保持安全, 避免在网上的不良经历? 2. I’m not an expert, but many years as a blogger have taught me a thing or two. 我不是专家, 但作为一个博主, 我已经学了好几年了。 3. If you see or read something that makes you feel uncomfortable, leave the site immediately. 如果你看到或读到一些让你觉得不舒服的东西, 立即离开这个网站。4. Don’t give out your address or phone number. 别告诉别人你的地址或电话号码。 5. Identity theft is a common and serious problem. 身份盗窃是一个常见而严重的问题。6. Being online is no excuse for being rude, and you don’t want to become a target for a troll or cyberbully. 上网并不是无礼的借口, 你也不想成为发挑衅帖子的人或网络恶霸的目标。 7. Trolls often use several false names so that they can stay on a site. 发挑衅帖子的人经常使用几个假名, 这样他们就可以留在一个网站上。8. However, the more polite you are, the less likely it is you will be attacked. 然而, 你越有礼貌, 你被攻击的可能性就越小。
新人教版高中英语必修2Unit 5 Music-Reading and Thinking教案一
This section focuses on "learning about experiencing music Online". This virtual choir is a new form of music performance. Members from all over the world don't need to love to come to a place. Instead, they use the new technology to model the various parts and wonderful virtual harmony group of music in the family. Students need to understand the main meaning of each paragraph. Finding topic sentences is an important way to understand the general idea of a paragraph. After the topic sentence, it is usually the detail sentence that supports and explains the topic sentence. Some paragraphs have obvious subject sentences, for example, the first sentence of the second paragraph is the subject sentence of the paragraph, and the following sentenceStudents need to pay attention to the topic sentences and key sentences, and then pay attention to how the sentences after the meaning explain, explain and support the topic sentences or key sentences before.1.Guide students to learn about experiencing music online2.Guide students to scan and circle the information in the text.3.Guide students to find the numbers and dates to fill in the timeline.4.Guide students to learn more about music by completing the sentences with the correct forms of the words and phrases. And then make a mind map about the outline of the passage.1. Guide students to pay attention to reading strategies, such as prediction, self-questioning and scanning.2. Help students sort out the main meaning of each paragraph and understand the narrative characteristics of "timeline” in illustrative style.3. Lead students to understand the changes that have been caused by the Internet.
人教版高中地理必修1第一章第一节宇宙中的地球教案
【总结讲解】地球为生命物质的存在提供了三个最优越的条件，这也是其它行星不具备的条件——（1）日地距离适中(1．496亿km)，使地表平均气温为15℃，有利于生命过程的发生和发展；地球上的温度，还有利于水的液态存在。适合生物呼吸的大气： （2） 地球的体积、质量适中，吸引大量气体聚集在地球周围，又经过漫长的演化，形成了以氮、氧为主的适合生物呼吸的大气。（3）海洋的形成： 由于地球内部放射性元素衰变致热和原始地球重力收缩及地球内部的物质运动等形成了原始大洋，地球最初的单细胞生命就出现在大洋中。（备注：此部分可以模拟演示或讲解地球存在生命的温度、大气、水等条件；假设地球温度过高或过低对地球生命的影响；引导学生分析地球大气、温度与地球水的关系）【板书】1、日地距离适中2、地球的体积、质量适中3、液态水的存在【启发提问】 宇宙中是否只有地球上存在有生命物质？
高中思想政治人教版必修四《哲学史上的伟大变革活动探究型》教案
一、教材分析人教版高中思想政治必修4生活与哲学第一单元第三课第二框题《哲学史上的伟大变革》。本框主要内容有马克思主义哲学的产生和它的基本特征、马克思主义的中国化的三大理论成果。学习本框内容对学生来讲，将有助于他们正确认识马克思主义，运用马克思主义中国化的理论成果，分析解决遇到的社会问题。具有很强的现实指导意义。二、学情分析高二学生已经具备了一定的历史知识，思维能力有一定提高，思想活跃，处于世界观、人生观形成时期，对一些社会现象能主动思考，但尚需正确加以引导，激发学生学习马克思主义哲学的兴趣。三、教学目标1.马克思主义哲学产生的阶级基础、自然科学基础和理论来源,马克思主义哲学的基本特征。2.通过对马克思主义哲学的产生和基本特征的学习，培养学生鉴别理论是非的能力，进而运用马克思主义哲学的基本观点分析和解决生活实践中的问题。3.实践的观点是马克思主义哲学的首要和基本的观点，培养学生在实践中分析问题和解决问题的能力，进而培养学生在实践活动中的科学探索精神和革命批判精神。