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人教版高中英語必修3Canada-the true north說課稿4篇
Good afternoon, teachers, It’s my great pleasure to be here sharing my lesson with you.The content of my lesson is Senior English Book 3 Unit 5 Canada —— “The true North”.I’ll be ready to begin this lesson from five parts. Analysis of the teaching material,the teaching methods,the studying methods, the teaching procedure,and Blackboard design.First, let me talk about the teaching material.Part 1 Teaching Material:This unit is about the introduction of Canada. By studying of this unit,we’ll enable the students to learn the geography, population, main cities, and natural beauty, natural resources of Canada. Through the training of the unit, it also requires students to learn some Language skills such as the expressions of position and emotions.So it plays an important part in the English teaching in this book.After studying the teaching material and analyzing the rule of children’s growing of mind,I think the teaching aims are the followings:1.Knowledge objects:(1) make the students learn some new words and phrases(2) make the students understand the content of the lesson.2.Ability objects:(1)To develop the Ss’ abilities of listening, speaking, reading and writing. Especially reading and speaking ability.(2) learn to talk about the characters of Canada in English(3)To train the Ss’ ability of working in pairs.3.Emotion objects:(1)Enable students to understand the characters of Canada..(2)Stimulate Ss to work hard to make China stronger.Part 2 Teaching Methods:I think helping students learn to master new words and phrases and improve the students’ reading and speaking ability is import and the difficult.According to the analysis of the teaching material and the import points and the difficult points,I will use the following teaching methods : question-guiding approach; fast-reading and careful reading; multi-media teaching methods; discussion
人教版高中英語必修3Festivals around the World說課稿3篇
Teaching plan for Unit 1 book3Good morning, teachers. It’s my great pleasure to be here because I can share my lesson with you and I can learn a lot from it. I’ll begin my lesson from the following four parts， the teaching material, the teaching methods, the studying methods and the teaching procedure.Firstly, let me talk about the teaching material. The content of my lesson is the reading passage festivals and celebrations of Unit 1 Festivals around the world. This passage is about festivals and celebrations. By studying this passage, we’ll enable the students to know that festivals exit everywhere, and many of festivals in different countries celebrate similar ideas. As we all know, the reading passage is the center of each unit. If the Ss can learn it well, it will be helpful to make the Ss learn the rest of this unit.After studying the teaching material, I think the teaching aims are as the followings:1. Knowledge aims:(1) The Ss can master the usage of the important words andexpressions.(2)The Ss can use the __________________ (grammar) in the proper situation.Make students know about the festivals all over the world and the detail of the festivals, such as origin, content, and the date of the holiday festivals.2. Ability aims:(1) Students can talk about festivals and celebrations in English(2) To improve the student’s reading ability, especially their skimming and scanning ability.3. Emotion aims:Make the Ss know about the foreign festivals, and respect other countries’ custom.Next, let’s come to the important points and the difficult points.The important point is how to make the Ss understand the text better and the difficult point is how can they talk about it. secondly， Teaching Methods:1. task-based Language Teaching2. Computer assisted language teaching.3. question-and–answer methodThirdly， Studying Methods:
人教版高中英語必修4Theme parks說課稿3篇
The oldest and the most popular park in the worldenjoy the exciting activities thereget close to the life-size cartoon characters like Mickey Mouse and Donald Duck Step 3 Pre-reading1.What do you suppose a theme park is ?2.What do you think you can see in a theme park?(1.It is a kind of amusement park which has a certain theme – that the whole park is based on. 2.buildings, castles, statues, rare animals and birds, and so on.) Step 4 Reading ----- Theme Parks –---- Fun and More Than Fun1.Predict : Read the title and the pictures on P. 34 and PredictWhat is the meaning of the title “Theme Park – Fun and more than fun”?(The title means that theme parks are fun to visit, but that they can also be educational and can offer useful information.)2.Skimming Fast read and answer:What activities can we take in a theme park?Amusement park: Bumper car Merry-go-round slide bungee jumping Free-fall rides Horror films Pirate ship Ferris wheel roller coaster3.Scanning Read again and you will find various theme parks are mentioned in the passage . Then what are they ?Theme parks: Sports theme park History theme park Culture theme park Marine or Ocean theme Park Future park Science theme park Disneyland4.Careful reading and find the main idea of each paragraph:THEME PARKS---- entertaining/ educationalPara.1 Traditional parks are places to go for relaxation and to have time away from our busy lives.Para.2 Theme parks are different They’re large and full of things to do, see and buy.Para.3 Theme parks are built around a single idea or theme. One example is a sports park.Para.4 Another kind of theme park is historical more and cultural and can be educational.Para.5 Disneylandwas the first theme park. It is based on the fantasy life and characters of Disney’s films.Para.6 Some examples of educational theme parks include sea world parks and science parks.
人教版高中英語必修4Working The Land說課稿3篇
Knowledge objectives:(1) to make Ss grasp the usage of words, expressions and sentence structures: statistics, struggle, thanks to, rid of, some patterns for persuasion, the “ing” form as subject and object;(2)to use learnt knowledge to persuade sb.Ability objectives:(1) to develop Ss’ reading skills(skimming, scanning, word guessing);(2) to improve Ss’ speaking, communicating and cooperating skills.Emotional objectives:to make Ss know the contribution of Yuan,and learn his spirit and his simple life time.Teaching important and difficult points:(1) some words, expressions and sentence structures mentioned above;(2)the content of the text;(3)training their reading and speaking skills.Teaching methods: CLT, TBLT,QT.Learning strategies: CLS, QLS, TBLS.Teaching procedures:Step 1 lead-in: (1) teacher plays a piece of recent news from CCTV about the harvest of the super hybrid rice, and ask students whether they know Yuan or not, and talk about him and his contribution.(2)Brain storm: let Ss describe Yuan in their minds including his appearance, his living condition and so on.Step 2 fast reading tasks:(1)teacher introduces Yuan and super hybrid rice(2)make Ss read the text as fast as possible with questions. Such as: what’s the general ideaof this passage? What’s Yuan’ dream? (skimming and scanning skill)Step 3 intensive reading tasks(1)let Ss read the text silently, find topic sentence of each paragraph and draw the difficult sentences and the knowledge what they don’t understand.(words guessing)(2)teacher and Ss talk about the important words, expressions and sentences together, and ask Ss to retell the content of the text.(summarizing and paraphrasing)(3)teacher summarize this part.(4) read again following the courseware.
人教版高中英語必修3The million pound bank note說課稿3篇
在接下來的細讀環(huán)節(jié)，我套用了高考對閱讀理解的考查方式設置了5個問題，分別為三個推理判斷題，一個細節(jié)題和一個主旨大意題。學生需要對文章的內容進行分析、歸納、推理、猜測等高級思維活動才能做出正確的回答?！驹O計意圖】這一過程是對學生進行細讀的訓練，培養(yǎng)學生獲取特定信息和挖掘文章深層次信息的能力。第三環(huán)節(jié):Intensive-reading (精讀) 15′第三個環(huán)節(jié)精讀，既是最重要的環(huán)節(jié)，也是突破本課重難點的關鍵。首先，讓學生思考劇本中人物看到百萬英鎊前后的態(tài)度發(fā)生了怎樣的變化。其次，讓學生仔細閱讀文章，找出可以表現(xiàn)人物態(tài)度變化的具體的語言和動作。最后，讓學生總結人物的態(tài)度發(fā)生變化的根本原因是什么，從而引出Money Talks, 供學生思考?！驹O計意圖】通過一系列的活動培養(yǎng)學生學習從人物的語言和動作探究人物的心理，使學生進一步體會戲劇語言的魅力，從而對文章背后所反映的社會問題進行思考，也為下一步的討論環(huán)節(jié)做好鋪墊。
人教版高中英語必修5Life in the Future說課稿5篇
Good afternoon, everyone. It’s my great pleasure to be here sharing my lesson with you. The content of my lesson is Senior English for China Book5 Unit 3 Life in the Future. I’ll be ready to begin this lesson from six parts: Analysis of the teaching material, Analysis of the students, Teaching aims and important and difficult points, Teaching methods and aids, Teaching procedures, and Blackboard design. First, let me talk about the teaching material.Part 1 Analysis of the Teaching Material:This unit is about what human beings’ life will be like in about one thousand years. By studying of this unit, we’ll Enable the students to know the changes in humans’ life and some new inventions bringing about the change and develop the interest in science. This lesson plays an important part in the English teaching in this unit. This is an important lesson in Book Five. From this lesson, it starts asking the Ss to grasp contents of each passage. Therefore, this lesson is in the important position of the teaching material. If the Ss can learn it well, it will be helpful to make the Ss learn the rest of this unit.Part 2 Analysis of the SsAs Senior2 Ss, they are at different levels of English fluency, some of them have lost interest in English. So during the lesson, I arrange a variety of activities to let all of them join in to attract their interest and let them be confident and taste the joy of success.
人教版高中英語必修5The United Kingdom說課稿4篇
Teaching Aims:Knowledge 1. Get the students to learn the useful new words and expressions in this section. Aims:2. Let the students learn about how the UK was formed and the four groups of invaders.1. Develop students’ reading ability and let them learn different Ability reading skills. Aims:2. Enable students to learn to talk about the United Kingdom and the Union Jack Emotional 1. Let students know more about the UK2. Develop students’ sense of cooperative learning Aims:Teaching Important Points:1. Let the students learn about the countries of the United Kingdom and the Union Jack2. Get the students to read the passage and know about how the UK was formed and the four groups of invaders.3. Have the students learn different reading skills.Teaching Difficult Ponts:1. Develop students’ reading ability.2. Enable students to talk about the United Kingdom and the Union Jack.3. Let students learn how the UK was formed geographically and historically.Teaching Methods:Showing pictures, asking, exercising, listening, reading etc.Teaching Aids:A computer,a projector and a blackboard.Teaching Procedures: 1) Show a map of the world, ask students the following questions:Where is the UK?What’s the full name of the UK?2) Ask the students work in pairs to do the quiz on Page 9.Do you want to test how many things you know about the United Kingdom? Let’s have a small test.Using the map on P9, students answer the following questions:?How many countries does the UK consist of? What are they??England is divided into three main areas. Do you know what they are? 1) Scanning (10Minutes )Let the students hold the questions asked in pre-reading and read the passagequickly and then let them do the following exercise.Join lines to the right answer.
鄉(xiāng)2023年人居環(huán)境整治上半年工作總結和下半年工作計劃
一、工作開展情況 （1）“五清一改”整治工作。全鄉(xiāng)扎實開展農村人居環(huán)境整治專項活動，鄉(xiāng)美麗辦開展人居環(huán)境整治國道和縣道巡查5次，通報3次，交辦整治任務30余項，河溝渠塘清淤40條約17公里，發(fā)動群眾投工投勞935人，清理亂搭亂建68處共計1233平米，有效整治了道路沿線有礙觀瞻的無功能建筑物，清除破舊廣告牌237余塊，開展入村宣傳450余次，發(fā)放相關宣傳單2000余份。清理農村生活垃圾743噸，同時清理農村生產(chǎn)廢棄物32噸，村莊整治收到良好效果。 （2）美麗鄉(xiāng)村建設工程。2020年省級美麗鄉(xiāng)村柏山村左家榨中心村和孤峰村孤峰中心村已完成項目驗收，正在等待縣級報賬。2021年市級美麗鄉(xiāng)村泉水村塘埂中心村已完成項目驗收，正在等待縣級報賬。2021年省級美麗鄉(xiāng)村華盤村油榨中心村建設項目施工方已進場施工，目前已完成亮化工程、古井節(jié)點打造、游步道鋪設、休閑游園建設，正在進行污水管網(wǎng)的鋪設和衛(wèi)生改廁。2023年市級美麗鄉(xiāng)村項目已批復，為泉水村河北中心村和景山村山榜中心村，目前已完成第一輪造價，正在準備招投標事宜。*鄉(xiāng)2021年孤峰村、華盤村“生態(tài)美”超市已完成建設并投入使用，正在準備2023年新橋村“五美”超市。 （3）改廁工作。2023年我鄉(xiāng)10個村共有改廁任務700戶，于2023年5月26日-5月27日進行了招投標，截止6月10日已完成改廁392戶，預計7月初完成全部改廁任務，后續(xù)將開展驗收和審計工作。對2021年300戶改廁進行了排查，發(fā)現(xiàn)3處問題，已安排整改完畢。（4）示范點建設情況。*鄉(xiāng)根據(jù)我鄉(xiāng)實際，每個行政村選擇了一到兩個村民組進行全覆蓋、高標準進行整治，樹立整治典型，起到模范作用。目前已完成整治17個示范點，部分示范點達到美麗鄉(xiāng)村標準，并實現(xiàn)了百姓參與、家禽圈養(yǎng)。
優(yōu)化營商環(huán)境服務中心民營經(jīng)濟服務工作總結（街道）
一、堅持疫情防控常態(tài)化，全面支持企業(yè)復工復產(chǎn)新年伊始，**街道春潮涌動，各行各業(yè)相繼開工趕生產(chǎn)，為實現(xiàn)首季“開門紅”，**街道堅持疫情防控常態(tài)化，以重點項目建設、重點企業(yè)服務為抓手，提前謀劃、集中發(fā)力、強化措施，瞄準全年目標任務，狠抓全年經(jīng)濟工作，支持企業(yè)員工留崗，全力助推轄區(qū)企業(yè)復工復產(chǎn)，保障轄區(qū)經(jīng)濟發(fā)展穩(wěn)中推進。今年以來，街道與企業(yè)、項目單位積極對接，在積極做好疫情防控工作的同時，鼓勵企業(yè)抓緊全面復工復產(chǎn)。為支持疫情期間經(jīng)濟發(fā)展，鼓勵及早復工，依據(jù)《關于下達**市規(guī)上服務業(yè)企業(yè)外省員工新春留崗獎勵資金的通知》（筑發(fā)改三產(chǎn)〔****〕***號）、《**市財政局**市商務局關于下達**市****年限額以上批零餐企業(yè)外省員工新春留崗獎勵資金的通知》（筑財建〔****〕**號）文件要求，街道積極組織轄區(qū)企業(yè)開展扶持獎勵申報，以高效、便捷、規(guī)范為原則，采取實地走訪、電話走訪等多種形式全力做好春節(jié)期間企業(yè)外省員工留崗獎勵的宣傳和申報工作，期間共宣傳通知企業(yè)***余家，搜集符合條件的申報企業(yè)資料**家，合計申報人數(shù)***人，實際審批通過人數(shù)***人，發(fā)放兌現(xiàn)新春留崗獎勵合計**萬元。
人教版新課標高中物理必修1速度變化快慢的描述─加速度說課稿2篇
本來比較速度變化的快慢也有兩種方法：一種是比較相同時間內速度變化量的大??；另一種是比較發(fā)生相同的速度變化所需要的時間長短。但教材是將比較質點位置移動快慢的思想直接遷移過來，通過實例分析，使學生明白不同運動物體的速度變化快慢不同，表現(xiàn)在速度的變化與發(fā)生這個變化所用時間的比值不同，從而引入加速度的定義方法a=△v/△t。加速度表示速度的變化快慢，包括速度增加的快慢和減小的快慢，不能誤認為只要有加速度的運動速度就一定是增加的。廣義地講，加速度不僅可以描述速度大小的變化快慢，而且也可以描述速度方向變化的快慢，本節(jié)教材只限定在直線運動的情景中討論。加速度的矢量性是一個難點，教材是以與速度方向相同或是相反來表述加速度的矢量性的。如果以初速度方向為正方向，那么加速度就有正負之分，加速度的正負表示加速度的方向，不表示加速度的大小。
人教版新課標高中物理必修1探究小車速度隨時間變化的規(guī)律說課稿2篇
（三）合作交流能力提升教師：剛才我們通過實驗了解了小車的速度是怎樣隨時間變化的，但實驗中有一定的誤差，請同學們討論并說出可能存在哪些誤差，造成誤差的原因是什么？（每個實驗小組的同學之間進行熱烈的討論）學生：測量出現(xiàn)誤差。因為點間距離太小，測量長度時容易產(chǎn)生誤差。教師：如何減小這個誤差呢？學生：如果測量較長的距離，誤差應該小一些。教師：應該采取什么辦法？學生：應該取幾個點之間的距離作為一個測量長度。教師：好，這就是常用的取“計數(shù)點”的方法。我們應該在紙帶上每隔幾個計時點取作一個計數(shù)點，進行編號。分別標為：0、1、2、3……，測各計數(shù)點到“0”的距離。以減小測量誤差。教師：還有補充嗎？學生1：我在坐標系中描點畫的圖象只集中在坐標原定附近，兩條圖象沒有明顯的分開。學生2：描出的幾個點不嚴格的分布在一條直線上，還能畫直線嗎？
人教版高中語文必修3《愛的奉獻 學習議論中的記敘》說課稿
教學過程：（一）導入：課前放《愛的奉獻》歌曲，同時不斷播放一些有關“愛”的主題的圖片，渲染一種情感氛圍。師說：同學們，誰能說說這組圖片的主題應該是什么？生（七嘴八舌）：母愛，不對是親情……是友情、還有人與人互相幫助……那組軍人圖片是說保衛(wèi)國家，應該是愛國……那徐本禹和感動中國呢？…………生答：是關于愛的方面師說：不錯，是關于愛的方面。那么同學們，今天就以“愛的奉獻”為話題，來寫一篇議論文如何？生答：老師，還是寫記敘文吧。生答：就是，要不議論文寫出來也象記敘文。師問：為什么？生答：老師，這個話題太有話說了，一舉例子就收不住了，怎么看怎么象記敘文。生答：就是，再用一點形容詞，就更象了。眾人樂。師說：那么同學們誰能告訴我，為什么會出現(xiàn)這種問題？一生小聲說：還不是我們笨，不會寫。師說：不是笨，也不是不會寫，你們想為什么記敘文就會寫，一到議論文就不會了，那是因為同學們沒有明白議論文中的記敘與記敘文中的記敘有什么不同，所以一寫起議論文中的記敘，還是按照記敘文的寫法寫作，這自然就不行了。那好，今天我們就從如何寫議論文中的記敘講起。
人教版高中政治必修4時代的精神的精華說課稿
（二）能力目標培養(yǎng)學生運用哲學理論觀察、分析、處理社會問題的能力，增強學生的時代感。（三）情感、態(tài)度與價值觀目標培養(yǎng)學生與時俱進的思想品質，讓學生關注時代、關注現(xiàn)實、關注生活，逐步樹立科學的世界觀、人生觀、價值觀。三、說教學重難點：時代精神的總結和升華是本框的難點，雖然學生在文化生活中學習了文化與經(jīng)濟政治的關系，但要讓學生得出哲學是時代精神的總結和升華，還要聯(lián)系前面關于哲學的基礎知識進行總結歸納，因此可能會難以把握，另外關于什么樣的哲學是真正的哲學的理解會稍有難度。社會變革的先導是本框的重點，一方面哲學源于時代，另一方面強調哲學反過來對時代又有重要的反作用，突出這一點能夠更好地激發(fā)學生學習哲學的熱情和信心，對于后面知識的學習是極為有益的，因此社會變革的先導這一目作重點處理。
人教A版高中數(shù)學必修一不同函數(shù)增長的差異教學設計（2）
本節(jié)課在已學冪函數(shù)、指數(shù)函數(shù)、對數(shù)函數(shù)的增長方式存在很大差異.事實上，這種差異正是不同類型現(xiàn)實問題具有不同增長規(guī)律的反應.而本節(jié)課重在研究不同函數(shù)增長的差異.課程目標1.掌握常見增長函數(shù)的定義、圖象、性質,并體會其增長的快慢.2.理解直線上升、對數(shù)增長、指數(shù)爆炸的含義以及三種函數(shù)模型的性質的比較,培養(yǎng)數(shù)學建模和數(shù)學運算等核心素養(yǎng).數(shù)學學科素養(yǎng)1.數(shù)學抽象：常見增長函數(shù)的定義、圖象、性質；2.邏輯推理：三種函數(shù)的增長速度比較；3.數(shù)學運算：由函數(shù)圖像求函數(shù)解析式；4.數(shù)據(jù)分析：由圖象判斷指數(shù)函數(shù)、對數(shù)函數(shù)和冪函數(shù)；5.數(shù)學建模：通過由抽象到具體，由具體到一般的數(shù)形結合思想總結函數(shù)性質.重點：比較函數(shù)值得大??；難點：幾種增長函數(shù)模型的應用．教學方法：以學生為主體，采用誘思探究式教學，精講多練。教學工具：多媒體。
人教A版高中數(shù)學必修一對數(shù)函數(shù)的圖像和性質教學設計（1）
本節(jié)課是新版教材人教A版普通高中課程標準實驗教科書數(shù)學必修1第四章第4.4.2節(jié)《對數(shù)函數(shù)的圖像和性質》 是高中數(shù)學在指數(shù)函數(shù)之后的重要初等函數(shù)之一。對數(shù)函數(shù)與指數(shù)函數(shù)聯(lián)系密切，無論是研究的思想方法方法還是圖像及性質，都有其共通之處。相較于指數(shù)函數(shù)，對數(shù)函數(shù)的圖象亦有其獨特的美感。在類比推理的過程中，感受圖像的變化，認識變化的規(guī)律，這是提高學生直觀想象能力的一個重要的過程。為之后學習數(shù)學提供了更多角度的分析方法。培養(yǎng)和發(fā)展學生邏輯推理、數(shù)學直觀、數(shù)學抽象、和數(shù)學建模的核心素養(yǎng)。1、掌握對數(shù)函數(shù)的圖像和性質；能利用對數(shù)函數(shù)的圖像與性質來解決簡單問題;2、經(jīng)過探究對數(shù)函數(shù)的圖像和性質，對數(shù)函數(shù)與指數(shù)函數(shù)圖像之間的聯(lián)系，對數(shù)函數(shù)內部的的聯(lián)系。培養(yǎng)學生觀察問題、分析問題和歸納問題的思維能力以及數(shù)學交流能力；滲透類比等基本數(shù)學思想方法。
點到直線的距離公式教學設計人教A版高中數(shù)學選擇性必修第一冊
4.已知△ABC三個頂點坐標A(－1,3)，B(－3,0)，C(1,2)，求△ABC的面積S.【解析】由直線方程的兩點式得直線BC的方程為 ＝ ，即x－2y＋3＝0，由兩點間距離公式得|BC|＝ ，點A到BC的距離為d，即為BC邊上的高，d＝ ，所以S＝ |BC|·d＝ ×2 × ＝4，即△ABC的面積為4.5.已知直線l經(jīng)過點P(0,2),且A(1,1),B(-3,1)兩點到直線l的距離相等,求直線l的方程.解:(方法一)∵點A(1,1)與B(-3,1)到y(tǒng)軸的距離不相等,∴直線l的斜率存在,設為k.又直線l在y軸上的截距為2,則直線l的方程為y=kx+2,即kx-y+2=0.由點A(1,1)與B(-3,1)到直線l的距離相等,∴直線l的方程是y=2或x-y+2=0.得("|" k"-" 1+2"|" )/√(k^2+1)=("|-" 3k"-" 1+2"|" )/√(k^2+1),解得k=0或k=1.(方法二)當直線l過線段AB的中點時,A,B兩點到直線l的距離相等.∵AB的中點是(-1,1),又直線l過點P(0,2),∴直線l的方程是x-y+2=0.當直線l∥AB時,A,B兩點到直線l的距離相等.∵直線AB的斜率為0,∴直線l的斜率為0,∴直線l的方程為y=2.綜上所述,滿足條件的直線l的方程是x-y+2=0或y=2.
兩點間的距離公式教學設計人教A版高中數(shù)學選擇性必修第一冊
一、情境導學在一條筆直的公路同側有兩個大型小區(qū),現(xiàn)在計劃在公路上某處建一個公交站點C,以方便居住在兩個小區(qū)住戶的出行.如何選址能使站點到兩個小區(qū)的距離之和最小?二、探究新知問題1.在數(shù)軸上已知兩點A、B，如何求A、B兩點間的距離？提示：|AB|＝|xA－xB|.問題2：在平面直角坐標系中能否利用數(shù)軸上兩點間的距離求出任意兩點間距離？探究.當x1≠x2，y1≠y2時，|P1P2|＝？請簡單說明理由．提示：可以，構造直角三角形利用勾股定理求解．答案：如圖，在Rt △P1QP2中，|P1P2|2＝|P1Q|2＋|QP2|2，所以|P1P2|＝?x2－x1?2＋?y2－y1?2.即兩點P1(x1，y1)，P2(x2，y2)間的距離|P1P2|＝?x2－x1?2＋?y2－y1?2.你還能用其它方法證明這個公式嗎？2．兩點間距離公式的理解(1)此公式與兩點的先后順序無關，也就是說公式也可寫成|P1P2|＝?x2－x1?2＋?y2－y1?2.(2)當直線P1P2平行于x軸時，|P1P2|＝|x2－x1|.當直線P1P2平行于y軸時，|P1P2|＝|y2－y1|.
兩條平行線間的距離教學設計人教A版高中數(shù)學選擇性必修第一冊
一、情境導學前面我們已經(jīng)得到了兩點間的距離公式，點到直線的距離公式，關于平面上的距離問題，兩條直線間的距離也是值得研究的。思考1：立定跳遠測量的什么距離？A.兩平行線的距離 B.點到直線的距離 C. 點到點的距離二、探究新知思考2：已知兩條平行直線l_1,l_2的方程，如何求l_1 〖與l〗_2間的距離？根據(jù)兩條平行直線間距離的含義，在直線l_1上取任一點P（x_0,y_0 ），,點P（x_0,y_0 ）到直線l_2的距離就是直線l_1與直線l_2間的距離，這樣求兩條平行線間的距離就轉化為求點到直線的距離。兩條平行直線間的距離1. 定義：夾在兩平行線間的__________的長.公垂線段2. 圖示： 3. 求法：轉化為點到直線的距離.1．原點到直線x＋2y－5＝0的距離是( )A．2 B．3 C．2 D．5D [d＝|－5|12＋22＝5.選D.]
圓的標準方程教學設計人教A版高中數(shù)學選擇性必修第一冊
(1)幾何法它是利用圖形的幾何性質,如圓的性質等,直接求出圓的圓心和半徑,代入圓的標準方程,從而得到圓的標準方程.(2)待定系數(shù)法由三個獨立條件得到三個方程,解方程組以得到圓的標準方程中三個參數(shù),從而確定圓的標準方程.它是求圓的方程最常用的方法,一般步驟是:①設——設所求圓的方程為(x-a)2+(y-b)2=r2;②列——由已知條件,建立關于a,b,r的方程組;③解——解方程組,求出a,b,r;④代——將a,b,r代入所設方程,得所求圓的方程.跟蹤訓練1．已知△ABC的三個頂點坐標分別為A(0,5)，B(1，－2)，C(－3，－4)，求該三角形的外接圓的方程．[解] 法一：設所求圓的標準方程為(x－a)2＋(y－b)2＝r2.因為A(0,5)，B(1,－2)，C(－3,－4)都在圓上，所以它們的坐標都滿足圓的標準方程，于是有?0－a?2＋?5－b?2＝r2，?1－a?2＋?－2－b?2＝r2，?－3－a?2＋?－4－b?2＝r2.解得a＝－3，b＝1，r＝5.故所求圓的標準方程是(x＋3)2＋(y－1)2＝25.
圓的一般方程教學設計人教A版高中數(shù)學選擇性必修第一冊
情境導學前面我們已討論了圓的標準方程為(x-a)2+(y-b)2=r2,現(xiàn)將其展開可得：x2+y2-2ax-2bx+a2+b2-r2=0.可見,任何一個圓的方程都可以變形x2+y2+Dx+Ey+F=0的形式.請大家思考一下,形如x2+y2+Dx+Ey+F=0的方程表示的曲線是不是圓?下面我們來探討這一方面的問題.探究新知例如,對于方程x^2+y^2-2x-4y+6=0,對其進行配方，得〖(x-1)〗^2+(〖y-2)〗^2=-1,因為任意一點的坐標 (x,y) 都不滿足這個方程，所以這個方程不表示任何圖形，所以形如x2+y2+Dx+Ey+F=0的方程不一定能通過恒等變換為圓的標準方程，這表明形如x2+y2+Dx+Ey+F=0的方程不一定是圓的方程.一、圓的一般方程（1）當D2+E2-4F>0時,方程x2+y2+Dx+Ey+F=0表示以(-D/2,-E/2)為圓心,1/2 √(D^2+E^2 "-" 4F)為半徑的圓,將方程x2+y2+Dx+Ey+F=0，配方可得〖(x+D/2)〗^2+(〖y+E/2)〗^2=(D^2+E^2-4F)/4（2）當D2+E2-4F=0時,方程x2+y2+Dx+Ey+F=0，表示一個點(-D/2,-E/2)（3）當D2+E2-4F0);
