-
新人教版高中英語必修1Unit 1 Teenage Life-Listening and Speaking & Listening and Talking教案
Step 2 Listening and Talking1. The teacher is advised to talk with their new students about the related topic: Boys and girls, do you know some structures to talk about future activities? Talking about future activitiesWe’ll …I plan to …There’ll be …I hope to …We’re going to …2. After their small talk, the teacher can move on by playing the listening and solve the following task.Underline the expressions in the sentences below Cao Jing and Max use to talk about the future.We’ll learn useful skills.I plan to improve my spoken English.There’ll be students from different schools.I hope to make new friends.We’ll talk about teenage life.I’ll learn to make a fire.There’ll be students from different countries at the camp.There’ll be some experts there to show us how to live in the wild.We’re going to learn about wildlife.I’m going to give a speech.I think I’m going to enjoy the activities.I think we’ll have a lot of fun.3. Work in groups. Plan a youth camp.Teacher make the Ss think of ideas for the camp. And they can use the questions below to get started. And have the Ss present their ideas for a youth camp to the class.●What kind of camp is it?●Who will be there?●What will they do?●What will they learn?
新人教版高中英語必修3Unit 1 Festivals and Celebrations-Reading and Thinking教學(xué)設(shè)計(jì)
The topic of this part is “Discover the reasons for festivals and celebrations.The Listening & Speaking & Talking part aims at talking about the experiences and feelings or emotions about the festivals and celebrations. This section aims at detecting the reason why the people celebrate the festivals, the time, the places, the types and the way of celebrations. It also explains why some traditions in the old celebrations are disappearing, like the firecrackers in the big cities and some new things are appearing like the prosperity of business or commerce. 1. Students can talk about what festivals they know and the reasons and the way of celebrating them.2. Students should learn the reading skills such as the headline and get the topic sentences, the structures of articles.3. Students can understand the past, the present situation of some festival around the world and why there are some changes about them. 4. Students can have the international awareness about the festivals.1. Students should learn the reading skills such as the headline and get the topic sentences, the structures of articles.2. Students can understand the past, the present situation of some festival around the world and why there are some changes about them.Step 1 Lead in---Small talkWhat festival do you like best ? Why ?I like the Spring Festivals because I can set off the fireworks, receive the lucky money and enjoy the Gala with my families.Step 2 Before reading---Pair workWhy do people celebrate different festivals ?The Spring Festivals is to celebrate the end of winter and the coming of spring and new life.The Mid-autumn Day is to celebrate the harvest and admire the moon.
新人教版高中英語必修3Unit 1 Festivals and Celebrations-Reading for writing教學(xué)設(shè)計(jì)二
Step 3 Analyzing article structureActivity 31. Teachers raise questions to guide students to analyze the chapter structure of this diary and think about how to describe the festival experience. (1)What should be included in the opening/body/closing paragraph(s)?(2)How did the writer arrange his/her ideas?(3)What kind of interesting details did the writer describe?(4)How did the writer describe his/her feelings/emotions during the event?2. Students read and compare the three sentence patterns in activity 2. Try to rewrite the first paragraph of the diary with these three sentence patterns. After that, students exchange corrections with their partners. Such as:●This was my first time spending three days experiencing the Naadam Festival in China’s Inner Mongolia Autonomous Region and it was an enjoyable and exciting experience. ●I'll never forget my experience at the Naadam Festival because it was my first time to watch the exciting Mongolian games of horse racing, wrestling, and archery so closely. ●I'll always remember my first experience at the Naadam Festival in China’s Inner Mongolia Autonomous Region because it was so amazing to spend three days witnessing a grand Mongolian ceremony. Step 4 Accumulation of statementsActivity 41. Ask the students to read the diary again. Look for sentences that express feelings and emotions, especially those with the -ing form and the past participle. Such as:● …h(huán)orse racing, wrestling, and archery, which are all so exciting to watch. ● some amazing performances● I was surprised to see…● I was a little worried about. . . ● feeling really tiredOther emotional statements:●I absolutely enjoyed the archery, too, but the horse races were my favourite part. ●I'm finally back home now, feeling really tired, but celebrating Naadam with my friend was totally worth it. ●He invited me back for the winter to stay in a traditional Mongolian tent and cat hot pot. I can’t wait!2. In addition to the use of the -ing form and the past participle, the teacher should guide the students in the appreciation of these statements, ask them to memorize them, and encourage them to use them reasonably in writing practice.
新人教版高中英語必修3Unit 3 Diverse Cultures-Discovering Useful Structure教學(xué)設(shè)計(jì)
Step 4 PracticeRead the conversation. Find out which words have been left out.Justin: Linlin, I’m going to Guizhou Province next month. I’m super excited! Any recommendations for places to visit?Linlin: Wow, cool! Guizhou is a province with a lot of cultural diversity. Places to visit...well, definitely the Huangguoshu Waterfall first.Justin: What’s special about the waterfall?Linlin: Well, have you ever heard of the Chinese novel Journey to the West ?Justin: Yes, I have. Why ?Linlin: In the back of the waterfall, you will find a cave, which is the home of the Monkey King.Justin: Really? Cool! I’ll definitely check it out.Linlin:And I strongly recommend the ethnic minority villages. You’ll find Chinese culture is much more diverse than you thought.Justin:Sounds great, thanks.Answers:Justin: Linlin, I’m going to Guizhou Province next month. I’m super excited! Do you have any recommendations for places to visit?Linlin: Wow, that’s cool! Guizhou is a province with a lot of cultural diversity. What are some places to visit in Guizhou ? Well, definitely the Huangguoshu Waterfall is the first place to visit in Guizhou Province.Justin: What’s special about the waterfall?Linlin: Well, have you ever heard of the Chinese novel Journey to the West ?Justin: Yes, I have heard of the Chinese novel Journey to the West . Why do you ask if I have heard of the Chinese novel Journey to the West?Linlin: In the back of the waterfall, you will find a cave, which is the home of the Monkey King from Journey to the West.Justin: That’s really true? It’s Cool! I’ll definitely check it out.Linlin:And I strongly recommend the ethnic minority villages on your trip to Guizhou Province. You’ll find Chinese culture is much more diverse than you thought it was.Justin:This all sounds great, thanks.
新人教版高中英語必修3Unit 3 Diverse Cultures-Listening &Speaking＆Talking教學(xué)設(shè)計(jì)
1. In Picture 1 and Picture 2, where do you think they are from? How do you know?From their wearings, we can know they are from ethnic minority of China--- Miao and Dong.Picture 1, they are playing their traditional instrument lusheng in their traditional costumes.Picture 2. the girls are Miao because they wear their traditional costumes and silver accessory.2. In Picture 3, can you find which village it is? What time is it in the picture?It is Dong village. It is at night. Step 2 While-listeningJustin met a new friend while traveling in Guizhou. Listen to their conversation and complete the summaries below.Part 1Justin and Wu Yue watched some Miao people play the lusheng. The instrument has a history of over 3,000 years and it is even mentioned in the oldest collection of Chinese poetry. Then they watched the lusheng dance. Justin wanted to buy some hand-made silver/traditional accessories as souvenirs. He was told that the price will depend on the percentage of silver. Part 2They will go to a pretty Dong minority village called Zhaoxing. they will see the drum towers and the wind and rain bridges. They may also see a performance of the Grand Song of the Dong people.Step 3 Post-listening---TalkingWork in groups. Imagine Justin is telling some friends about his trip to Guizhou. One of you is Justin and the rest of you are his friends. Ask Justin questions about his trip and experience. The following expressions may help you.
新人教版高中英語必修3Unit 4 Space Exploration-Listening&Speaking＆Talking教學(xué)設(shè)計(jì)二
The themes of this part are “Talk about how to become an astronaut” and “Talk about life in space”. As Neil Armstrong said “Mystery creates wonder and wonder is the basis of man’s desire to understand. Space is difficult for human to reach, therefore, humans are full of wonders about it. However, if wanting to achieve the dream of reaching the Moon, some of our human should work hard to be an astronaut at first. Part A(Talk about how to become an astronaut) is a radio interview in a radio studio, where the host asked the Chinese astronauts about his story how to become an astronaut. Yang Liwei told his dreamed to be an astronaut since childhood. Then he worked hard to get into college at 22. The next 10 years, he gradually became an experienced pilot. At the same time, to be an astronaut, he had to study hard English, science and astronomy and trained hard to keep in good physical and mental health and to practise using space equipment. Part B (Talk about life in space) is also an interview with the astronaut Brown, who is back on the earth. The host Max asked about his space life, such as his emotion about going back the earth, the eating, shower, brushing, hobbies and his work. Part A and Part B are interviews. So expressing curiosity about the guests’ past life is a communicative skill, which students should be guided to learn.1. Students can get detailed information about how Yang Liwei became an astronaut and Max’s space life.2. Students learn to proper listening strategy to get detailed information---listening for numbers and taking notes.3. Students can learn related sentences or phrases to express their curiosity like “ I wish to know...” “I’d love to know...”4. Students can learn more about the space and astronauts, even be interested in working hard to be an astronaut
新人教版高中英語必修3Unit 5 The Value of Money- Discovering Useful Structure教學(xué)設(shè)計(jì)
Step 3 Meaning1. 過去將來時表示從過去某一時間來看將要發(fā)生的動作或存在的狀態(tài), 常用在賓語從句中。一般由“would/should +動詞原形”構(gòu)成。She hoped that they would meet again someday. 她希望將來有一天他們能再見面。2. was/were going to+動詞原形: 表示過去將要發(fā)生或很有可能發(fā)生的動作, 常用于口語中, 表示預(yù)言、意圖或者打算等。He was going to start work the following week. 他打算下星期開始工作。3. was/were about to do: 常用來表示即將發(fā)生的動作, “剛要/正要做……”。注意該結(jié)構(gòu)不與任何時間狀語連用。I felt that something terrible was about to happen. 我感到某種可怕的事情即將發(fā)生。4.was/were to do: 表示“曾計(jì)劃做某事”, 如果表示“本來計(jì)劃做某事, 動作沒實(shí)現(xiàn)”, 則需用 “was/were to have done”。She said she was to have told me about the accident. 她說她本來想告訴我關(guān)于事故的事。5.Start, go, come, leave, see, meet等動詞的過去進(jìn)行時: 表示就過去某一時刻而言即將發(fā)生的動作。She was coming later. 她隨后就來。I had just put on my overcoat and was leaving to visit a friend of mine. 我剛穿上外套要去看我的一個朋友。
新人教版高中英語必修3Unit 5 The value of money-Reading and Thinking教學(xué)設(shè)計(jì)二
? Could you offer me some kind of work here?? I don’t want your charity, I just want an honest job.? Careless: I landed in Britain by accident.Step 7:Consolidation.? Find Henry? Roderick and Oliver were I .making a bet when they saw Henry, a poor young man. ? Know Henry? About a month ago, Henry was sailing and later he found himself carried out to sea by a strong wind. Fortunately, he 2.was spotted by a ship. And it was the ship that brought him to 3.England? Offer money to Henry ? Oliver and Roderick gave Henry a letter and told him that there was money in it. They 4.persuaded him to accept it, and made him 5.promise that it wouldn't be opened until 2 o'clock.Step 8：Language pointsa large amount of: a large quantity of; a great deal ofe.g. They bought a large amount of furniture before they moved their new house.make a bet: make an arrangement to risk money, etc. on an event of which the result is doubtful.e.g. We made a bet on the result of the match.permit sb to do something: allow somebody to do somethinge.g. My mother doesn’t permit me to ride in the street after it rained.by accident: as a result of chancee.g. I only found it by accident.stare at: look at somebody or something with the eyes wide open in a fixed gaze( in astonishment, wonder, fear, etc)to be honest: to tell you the truth; to be franke.g. To be honest, I don’t think we have a chance of winning.Step7 Homework:What do you think will happen to Henry? Will the bank-note help him or get him into trouble?
新人教版高中英語必修3Unit 5 the value of money-Reading For Writing教學(xué)設(shè)計(jì)一
【參考范文】Narrator：(Henry is smiling as he leaves the restaurant. As he is walking down the street, he sees a sign for a place that cuts hair. He decides to get it cut. )H＝Henry；B＝Barber；R＝rude manH：Good afternoon, I'd like to get a cut, if I may. (The barber looks at Henry's hair and continues cutting another man's hair. )Er, I'd really like a haircut. As you can see it's much too long. B：(in a rude manner) Yes, I can see that. Indeed, I can. H：Fine, well I'll have a seat then. (He sits in one of the barber's chairs. The barber turns to look at Henry. )B：It's quite expensive here, you know！Are you sure you can afford it?H：Yes. I think so. (In comes the rude man. )R：Hey you there. I need a haircut quickly. Can you do me straightaway?B：All right, then, get in the chair and I'll see what I can do. R：Thank you. (sits down in one of the barber's chairs)H：Excuse me, but I was here first. Aren't you going to do my hair first?B：This man's in a hurry. H：Well so am I！I insist that you cut my hair first. B：OK, but I'll have to be quick. This gentleman is waiting. H：Thank you. (They both become quiet. After his hair is cut, the barber tells Henry how much he must pay. Henry shows the barber the bank note. )B：Why, Mr . . . (looks shocked)H：Adams. Henry Adams. I'm sorry, I don't have any change. R：You're that Mr Adams! Well，I'm glad I waited or I might never have known it was you. B：Why, Mr Adams, please don't worry！(wearing a big smile) Nothing to worry about！Nothing at all!Please come back any time, even if you only need too little hairs cut！It will be my honour to serve you!
人教版高中數(shù)學(xué)選擇性必修二變化率問題教學(xué)設(shè)計(jì)
導(dǎo)語在必修第一冊中，我們研究了函數(shù)的單調(diào)性，并利用函數(shù)單調(diào)性等知識，定性的研究了一次函數(shù)、指數(shù)函數(shù)、對數(shù)函數(shù)增長速度的差異，知道“對數(shù)增長” 是越來越慢的，“指數(shù)爆炸” 比“直線上升” 快得多，進(jìn)一步的能否精確定量的刻畫變化速度的快慢呢，下面我們就來研究這個問題。新知探究問題1 高臺跳水運(yùn)動員的速度高臺跳水運(yùn)動中，運(yùn)動員在運(yùn)動過程中的重心相對于水面的高度h(單位：m)與起跳后的時間t(單位：s)存在函數(shù)關(guān)系h(t)＝－4.9t2＋4.8t＋11.如何描述用運(yùn)動員從起跳到入水的過程中運(yùn)動的快慢程度呢？直覺告訴我們，運(yùn)動員從起跳到入水的過程中，在上升階段運(yùn)動的越來越慢，在下降階段運(yùn)動的越來越快，我們可以把整個運(yùn)動時間段分成許多小段，用運(yùn)動員在每段時間內(nèi)的平均速度v ?近似的描述它的運(yùn)動狀態(tài)。
新人教版高中英語必修3Unit 5 The Value of Money-Discovering Useful Structures導(dǎo)學(xué)案
4．They were going to find someone to take part in their bet when they saw Henry walking on the street outside.[歸納]1．過去將來時的基本構(gòu)成和用法過去將來時由“would＋動詞原形”構(gòu)成，主要表示從過去某一時間來看將要發(fā)生的動作(尤其用于賓語從句中)，還可以表示過去的動作習(xí)慣或傾向。Jeff knew he would be tired the next day.He promised that he would not open the letter until 2 o'clock.She said that she wouldn't do that again.2．表示過去將來時的其他表達(dá)法(1)was/were going to＋動詞原形：該結(jié)構(gòu)有兩個主要用法，一是表示過去的打算，二是表示在過去看來有跡象表明將要發(fā)生某事。I thought it was going to rain.(2)was/were to＋動詞原形：主要表示過去按計(jì)劃或安排要做的事情。She said she was to get married next month.(3)was/were about to＋動詞原形：表示在過去看來即將要發(fā)生的動作，由于本身已含有“即將”的意味，所以不再與表示具體的將來時間狀語連用。I was about to go to bed when the phone rang.(4)was/were＋現(xiàn)在分詞：表示在過去看來即將發(fā)生的動作，通?？捎糜谠摻Y(jié)構(gòu)中的動詞是come，go，leave，arrive，begin，start，stop，close，open，die，join，borrow，buy等瞬間動詞。Jack said he was leaving tomorrow.
《故都的秋》《荷塘月色》《我與地壇》群文閱讀說課稿 2022-2023學(xué)年統(tǒng)編版高中語文必修上冊
(2) 中國文人的悲秋情結(jié)。3.《荷塘月色》中，作者為什么要離開家來到荷塘散步？4. 思考：作者的心里為何“頗不寧靜？”（教師補(bǔ)充：寫作背景）5. 出門散步后，作者的心情發(fā)生變化了嗎？ 有怎樣的變化？6.思考討論：為什么作者說“我”與“地壇”間有著宿命般的緣分，二者有何相似之處？（閱讀1-5段）7.思考：作者從他同病相憐的“朋友“身上理解了怎樣的”意圖“？三、課堂總結(jié)李白說：“天地者，萬物之逆旅也?！比松缤粓雎眯?，在人生的旅途中，時而高山，時而峽谷，時而坦途，時而歧路。我們或放歌，或悲哭，然而，大自然始終以其不變的姿勢深情地看著我們，而我們，也應(yīng)該學(xué)會在與自然的深情對望中，找到生命的契合。正如敬亭山之于李白，故都的秋之于郁達(dá)夫，荷塘月色之于朱自清，地壇之于史鐵生，他們從中或得到心靈的慰藉、精神的寄托，或得到生存的智慧與勇氣，最終完成精神的超脫。
《一個消逝了的山村》說課稿 2021—2022學(xué)年統(tǒng)編版高中語文選擇性必修下冊
這幾段內(nèi)容傳達(dá)出的是“要敬畏生命，尊重生命；更要敬畏大自然，尊重大自然，愛護(hù)大自然”的主旨內(nèi)涵，因此讓學(xué)生通過自由朗讀的方式，再次體會馮至對這個消逝了的山村的細(xì)致的美好的描繪，感悟馮至傳達(dá)出的對生命，對自然的理解和思考。5.最后一個自然段的解讀依然是交給學(xué)生，先齊讀課文，再讓學(xué)生自主分享自己的體會或疑惑。但在這一環(huán)節(jié)我也設(shè)計(jì)了兩個我認(rèn)為必須解答的兩個問題，一是怎么理解“在風(fēng)雨如晦的時刻”；二是“意味不盡的關(guān)聯(lián)”是指什么。我認(rèn)為這兩個問題一個涉及到寫作背景，一個涉及到對全文主旨的一個整體把握，能夠進(jìn)一步幫助學(xué)生理解散文的深刻內(nèi)涵和主旨，讓學(xué)生有意識的在閱讀散文過程中通過背景知識進(jìn)行理解。既尊重學(xué)生的個性化解讀，又能夠讓學(xué)生有意義學(xué)習(xí)，完成預(yù)設(shè)的教學(xué)目標(biāo)。如果學(xué)生沒有提到這兩處，那我就需要做出補(bǔ)充。
人教A版高中數(shù)學(xué)必修一函數(shù)的零點(diǎn)與方程的解教學(xué)設(shè)計(jì)（1）
本節(jié)課是新版教材人教A版普通高中課程標(biāo)準(zhǔn)實(shí)驗(yàn)教科書數(shù)學(xué)必修1第四章第4.5.1節(jié)《函數(shù)零點(diǎn)與方程的解》，由于學(xué)生已經(jīng)學(xué)過一元二次方程與二次函數(shù)的關(guān)系，本節(jié)課的內(nèi)容就是在此基礎(chǔ)上的推廣。從而建立一般的函數(shù)的零點(diǎn)概念，進(jìn)一步理解零點(diǎn)判定定理及其應(yīng)用。培養(yǎng)和發(fā)展學(xué)生數(shù)學(xué)直觀、數(shù)學(xué)抽象、邏輯推理和數(shù)學(xué)建模的核心素養(yǎng)。1、了解函數(shù)（結(jié)合二次函數(shù)）零點(diǎn)的概念；2、理 解函數(shù)零點(diǎn)與方程的根以及函數(shù)圖象與x軸交點(diǎn)的關(guān)系,掌握零點(diǎn)存在性定理的運(yùn)用；3、在認(rèn)識函數(shù)零點(diǎn)的過程中，使學(xué)生學(xué)會認(rèn)識事物的特殊性與一般性之間的關(guān)系，培養(yǎng)數(shù)學(xué)數(shù)形結(jié)合及函數(shù)思想； a.數(shù)學(xué)抽象：函數(shù)零點(diǎn)的概念；b.邏輯推理：零點(diǎn)判定定理；c.數(shù)學(xué)運(yùn)算：運(yùn)用零點(diǎn)判定定理確定零點(diǎn)范圍；d.直觀想象：運(yùn)用圖形判定零點(diǎn)；e.數(shù)學(xué)建模：運(yùn)用函數(shù)的觀點(diǎn)方程的根；
古詩詞誦讀《虞美人（春花秋月何時了）》說課稿 2021-2022學(xué)年統(tǒng)編版高中語文必修上冊
（一）說教材 《虞美人》選自高中語文統(tǒng)編版必修上冊·古詩詞誦讀?！队菝廊恕肥窃~中的代表作品，是李煜生命中最為重要的一首詞作，極具藝術(shù)魅力，對于陶冶學(xué)生的情操，豐富和積淀學(xué)生的人文素養(yǎng)意義非凡。（二）說學(xué)情總體來說，所教班級的學(xué)生基礎(chǔ)不強(qiáng)，學(xué)習(xí)意識略有偏差，在學(xué)習(xí)過程中需要教師深入淺出，不斷創(chuàng)造動口、動手、動腦的機(jī)會，他們才能更好地達(dá)成教學(xué)目標(biāo)。（三）說教學(xué)目標(biāo)根據(jù)教學(xué)內(nèi)容和學(xué)情分析，確定如下教學(xué)目標(biāo)（1）探究這首詞的內(nèi)涵，了解李煜及其創(chuàng)作風(fēng)格。（2）通過對本詞的品析，提高詞的鑒賞能力。（3）通過對比閱讀，體會李煜詞 “赤子之心” 、“以血書者”的特色，體味其深沉的亡國之恨和故國之思。
拋物線的簡單幾何性質(zhì)（2）教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊
二、直線與拋物線的位置關(guān)系設(shè)直線l:y=kx+m,拋物線:y2=2px(p>0),將直線方程與拋物線方程聯(lián)立整理成關(guān)于x的方程k2x2+2(km-p)x+m2=0.(1)若k≠0,當(dāng)Δ>0時,直線與拋物線相交,有兩個交點(diǎn);當(dāng)Δ=0時,直線與拋物線相切,有一個切點(diǎn);當(dāng)Δ<0時,直線與拋物線相離,沒有公共點(diǎn).(2)若k=0,直線與拋物線有一個交點(diǎn),此時直線平行于拋物線的對稱軸或與對稱軸重合.因此直線與拋物線有一個公共點(diǎn)是直線與拋物線相切的必要不充分條件.二、典例解析例5.過拋物線焦點(diǎn)F的直線交拋物線于A、B兩點(diǎn)，通過點(diǎn)A和拋物線頂點(diǎn)的直線交拋物線的準(zhǔn)線于點(diǎn)D，求證：直線DB平行于拋物線的對稱軸．【分析】設(shè)拋物線的標(biāo)準(zhǔn)方程為：y2＝2px（p＞0）．設(shè)A（x1，y1），B（x2，y2）．直線OA的方程為： ＝ ＝ ，可得yD＝ ．設(shè)直線AB的方程為：my＝x﹣ ，與拋物線的方程聯(lián)立化為y2﹣2pm﹣p2＝0，
雙曲線的簡單幾何性質(zhì)（2）教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊
二、典例解析例4．如圖，雙曲線型冷卻塔的外形，是雙曲線的一部分，已知塔的總高度為137.5m，塔頂直徑為90m，塔的最小直徑(喉部直徑)為60m，喉部標(biāo)高112.5m，試建立適當(dāng)?shù)淖鴺?biāo)系，求出此雙曲線的標(biāo)準(zhǔn)方程（精確到1m）解:設(shè)雙曲線的標(biāo)準(zhǔn)方程為 ，如圖所示：為喉部直徑，故 ，故雙曲線方程為 .而 的橫坐標(biāo)為塔頂直徑的一半即 ，其縱坐標(biāo)為塔的總高度與喉部標(biāo)高的差即 ，故 ，故 ，所以 ，故雙曲線方程為 .例5．已知點(diǎn) 到定點(diǎn) 的距離和它到定直線l: 的距離的比是 ，則點(diǎn) 的軌跡方程為?解：設(shè)點(diǎn) ，由題知, ，即 .整理得： .請你將例5與橢圓一節(jié)中的例6比較，你有什么發(fā)現(xiàn)？例6、 過雙曲線 的右焦點(diǎn)F2,傾斜角為30度的直線交雙曲線于A,B兩點(diǎn),求|AB|.分析:求弦長問題有兩種方法:法一:如果交點(diǎn)坐標(biāo)易求,可直接用兩點(diǎn)間距離公式代入求弦長;法二:但有時為了簡化計(jì)算,常設(shè)而不求,運(yùn)用韋達(dá)定理來處理.解：由雙曲線的方程得，兩焦點(diǎn)分別為F1(-3,0),F2(3,0).因?yàn)橹本€AB的傾斜角是30°，且直線經(jīng)過右焦點(diǎn)F2，所以，直線AB的方程為
橢圓的簡單幾何性質(zhì)（2）教學(xué)設(shè)計(jì)人教A版高中數(shù)學(xué)選擇性必修第一冊
二、典例解析例5. 如圖，一種電影放映燈的反射鏡面是旋轉(zhuǎn)橢圓面（橢圓繞其對稱軸旋轉(zhuǎn)一周形成的曲面）的一部分。過對稱軸的截口 ABC是橢圓的一部分，燈絲位于橢圓的一個焦點(diǎn)F_1上，片門位另一個焦點(diǎn)F_2上，由橢圓一個焦點(diǎn)F_1 發(fā)出的光線，經(jīng)過旋轉(zhuǎn)橢圓面反射后集中到另一個橢圓焦點(diǎn)F_2，已知 〖BC⊥F_1 F〗_2，|F_1 B|=2.8cm, |F_1 F_2 |=4.5cm,試建立適當(dāng)?shù)钠矫嬷苯亲鴺?biāo)系，求截口ABC所在的橢圓方程(精確到0.1cm)典例解析解：建立如圖所示的平面直角坐標(biāo)系，設(shè)所求橢圓方程為x^2/a^2 +y^2/b^2 =1 (a>b>0) 在Rt ΔBF_1 F_2中,|F_2 B|= √(|F_1 B|^2+|F_1 F_2 |^2 )=√(〖2.8〗^2 〖+4.5〗^2 ) 有橢圓的性質(zhì) , |F_1 B|+|F_2 B|=2 a, 所以a=1/2(|F_1 B|+|F_2 B|)=1/2(2.8+√(〖2.8〗^2 〖+4.5〗^2 )) ≈4.1b= √(a^2 〖-c〗^2 ) ≈3.4所以所求橢圓方程為x^2/〖4.1〗^2 +y^2/〖3.4〗^2 =1 利用橢圓的幾何性質(zhì)求標(biāo)準(zhǔn)方程的思路1．利用橢圓的幾何性質(zhì)求橢圓的標(biāo)準(zhǔn)方程時，通常采用待定系數(shù)法，其步驟是：(1)確定焦點(diǎn)位置；(2)設(shè)出相應(yīng)橢圓的標(biāo)準(zhǔn)方程(對于焦點(diǎn)位置不確定的橢圓可能有兩種標(biāo)準(zhǔn)方程)；(3)根據(jù)已知條件構(gòu)造關(guān)于參數(shù)的關(guān)系式，利用方程(組)求參數(shù)，列方程(組)時常用的關(guān)系式有b2＝a2－c2等．
人教A版高中數(shù)學(xué)必修二總體集中趨勢的估計(jì)教學(xué)設(shè)計(jì)
（2）平均數(shù)受數(shù)據(jù)中的極端值（2個95）影響較大，使平均數(shù)在估計(jì)總體時可靠性降低，10天的用水量有8天都在平均值以下。故用中位數(shù)來估計(jì)每天的用水量更合適。1、樣本的數(shù)字特征：眾數(shù)、中位數(shù)和平均數(shù)；2、用樣本頻率分布直方圖估計(jì)樣本的眾數(shù)、中位數(shù)、平均數(shù)。（1）眾數(shù)規(guī)定為頻率分布直方圖中最高矩形下端的中點(diǎn)；（2）中位數(shù)兩邊的直方圖的面積相等；（3）頻率分布直方圖中每個小矩形的面積與小矩形底邊中點(diǎn)的橫坐標(biāo)之積相加，就是樣本數(shù)據(jù)的估值平均數(shù)。學(xué)生回顧本節(jié)課知識點(diǎn)，教師補(bǔ)充。 讓學(xué)生掌握本節(jié)課知識點(diǎn)，并能夠靈活運(yùn)用。
人教A版高中數(shù)學(xué)必修二總體離散程度的估計(jì)教學(xué)設(shè)計(jì)
問題二：上述問題中，甲、乙的平均數(shù)、中位數(shù)、眾數(shù)相同，但二者的射擊成績存在差異，那么，如何度量這種差異呢？我們可以利用極差進(jìn)行度量。根據(jù)上述數(shù)據(jù)計(jì)算得：甲的極差=10-4=6 乙的極差=9-5=4極差在一定程度上刻畫了數(shù)據(jù)的離散程度。由極差發(fā)現(xiàn)甲的成績波動范圍比乙的大。但由于極差只使用了數(shù)據(jù)中最大、最小兩個值的信息，所含的信息量很少。也就是說，極差度量出的差異誤差較大。問題三：你還能想出其他刻畫數(shù)據(jù)離散程度的辦法嗎？我們知道，如果射擊的成績很穩(wěn)定，那么大多數(shù)的射擊成績離平均成績不會太遠(yuǎn)；相反，如果射擊的成績波動幅度很大，那么大多數(shù)的射擊成績離平均成績會比較遠(yuǎn)。因此，我們可以通過這兩組射擊成績與它們的平均成績的“平均距離”來度量成績的波動幅度。