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人教版高中政治必修4價值與價值觀說課稿（二）
二、學生情況分析(說學法)1、學生學習基礎(chǔ)分析：學生通過對《生活與哲學》前面三個單元的學習，初步掌握了運用唯物論、辯證法、認識論的觀點去認識問題、分析問題的能力；再通過對第十一課的學習，學生對馬克思主義的歷史觀有了初步的理解，初步樹立了正確的理想信念，這為本課教學目標的落實奠定了知識基礎(chǔ)。 2、學生能力分析 ：高二學生擁有一定生活體驗，具備一定的信息收集和篩選能力、閱讀能力、語言表達能力、對問題的一定的探究能力，同伴合作能力和具備初步邏輯思維能力。3、學生心理分析：在我國現(xiàn)階段，以為人民服務為核心的社會主義道德建設(shè)過程中涌現(xiàn)了大批的先進人物和道德典范，但同時由于社會價值的多元化，個人主義、享樂主義、拜金主義等資本主義腐朽思想也同樣在影響著當代的中學生。
人教版高中英語必修4Body Language說課稿4篇
Textbook: Senior English for China (Book 4), by Liu Daoyi Time Allotment: 1 period (40 minutes)Date: March 20, 2014Teaching aids: blackboard, Multi-media, Power Point, chalk I. Text Analysis （教材分析）This unit is about body language, and the text selected in the reading part demonstrates the difference and similarity of body language in many parts of the world. Through learning this passage, students are required to raise their awareness of using body language in different parts of the world. As body language is closely related to our daily life, it is easy to arouse students’ interest in learning this text. Reading skills and speaking training are designed around the text.II. Teaching Objectives （教學目標）By the end of the lesson, students will be able to:1. Language Skill Objective（語言技能目標）: develop reading ability （skimming and scanning）as well as speaking ability.2. Cultural Knowledge Objective（文化知識目標）: know about the cultural differences of using body language.3. Affective Objective（情感目標）: increase students’ awareness of using body language correctly in different cultures. III.Teaching Focuses and Difficulties（教學重點和難點）1. Teaching Focuses（教學重點）: the difference and similarity of body language in many parts of the world.2. Teaching Difficulties（教學難點）: develop students’ reading abilities of skimming and scanning and ask the students to show their opinions with fluent English.
人教版高中英語必修3Astronomy the science of the stars說課稿3篇
Step 2 Pre-listeningAfter students finish their discussion, I will show a picture of Newton and ask them: Who is him? What is he famous for? Could you find out some words to describe him? Maybe students will answer that he is genius for his finding of theGravitation, making a great contribution to the progress of human being. At that time I will show another two pictures of Einstein and Hawking, letting students guess who they are and write down their idea about the Gravitation. For I have arranged them to search more information about the gravity before this class, Students have beenfamiliar with the topic and will not be afraid about this abstract conception, which is helpful for their listening.Step 3 While-listeningIn this step, students will be required to listen the material for three times. The first and listening is extensive listening and the second and third listening is intensive listening. In the first time, They are required to listen a material including Part 1 and Part 2 and choose the best summary of the listening text. After they choose the right answer, They also need work in group to explain what is wrong with the others. Then I will make a conclusion that we should pay attention to the first paragraph and last paragraph and some keys to get the main idea. By doing this, their capacity of generalization will have a great improvement.Before the second listening, I will ask students to scan the blank on the power point quickly and ask them to note down some key words .Then ask them to listen to the Part 1again and fill the first column of the chart. Maybe some students just show the ideas of these three scientists an still can’t catch their development of gravity. Therefore, I will ask them to listen to Part 2 again and fill in the rest. After finish the listening, I will give them ten minutes to discuss with their partner. I will also guidethem to improve their answers when they discuss with others.
人教版高中英語必修4A taste of English Humor說課稿3篇
Then I would ask them to think of a funny English or Chinese and tell it to partners. While telling stories, they can use expressions and some acting to help make the story funny. 5 minutes would be given to do this.Those stories they told there will be the material for their writing. Soletting them tell it at first is helpful. And they can make a difference between telling a funny story and writing it down. Generally speaking, it is difficult forstudents to write well because they don’t know what to write and how to write. Asking them to tell their own stories at first can help them come up with what to write.After their telling, I would invite someone to share his/her story with all of us and I would write it down on the blackboard.This example story would be used as a sample to illustrate the format of funny story. Different from a story from teacher or textbook, a story from students can obviously become a interesting material to draw students’ attention.Then I would ask the whole class to put this story into several parts. It might be a little bit difficult for them. So I would ask them to find out whether all the sentences are necessary. After delete some sentences, there are 6 sentences left behind. Then they can easily put them into three parts. After interaction with students, I would teach them the right terms for each part and conclude the format of funny story.This step is the key and difficult point in my lesson. So I mainly usetask-based teaching method in this part and the task for students was divided into several stages. With the separated difficult level, students can find there are usually three parts in writing. They can also learn to write without the unnecessary parts in the process of analyzing. And then I wouldn’t rush to tell them the right terms to them directly. Instead, I would ask them to name them by their own. A confused mind is better for acquiring knowledge.While-writing:Then I would give students 7 minutes to write down this story, without other requirements.With all the preparations in pre-writing, students’ difficulties were cleared. So it would be much easier for them to write down the story within 7 minutes. There are no other requirements because students’ first writing is actually a drafting. It would be revise and edit several times later. Writing, as a skill
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5First aid說課稿6篇
In this class, I have 3 teaching aims, that is, knowledge aims, ability aims and emotion aims.1) Knowledge-Teach students new words and expressions, such as temporary, bleed,sprain choke, first aid, fall ill and so on.-Enable students to have a better understanding for some basic knowledge of first aid.2) Ability-Train students’ speaking, reading and writing abilities by different teaching activities, such as skimming, comprehending, team work, role play, retelling and writing.-Develop students’ reading strategy on how to move general idea to specific information.3) Emotion-Promote students’ awareness of giving first aid.- Cultivate students’ creativities.Then let’s come to my teaching methods and activities.III. Teaching methods and activities:To achieve different teaching aims, various kinds of teaching methods and activities will be adopted throughout this period, such as TBL (task-based learning), skimming, team work, brainstorm and others, which can offer students opportunities to fulfill tasks in which they can use language to achieve a specific outcome.IV. Teaching aids:Computer and blackboardV. Teaching important points:1) Make students have a clear mind for the structure of the text.2) Help students understand the theme of the text.VI. Teaching difficulties:1) So many new words may affect students’ understanding.2) How to get students to know about the functions of the skin and thecauses, characteristics and treatments for different degree burns,and the knowledge about giving first aid. VII. Blackboard design:
人教版高中英語必修5Making the news說課稿4篇
今天我們來介紹一下必修五第四單元的授課方式。這個單元的題目是Making the news。應該是學生比較感興趣的話題，學生往往對新聞工作充滿好奇，所以我們可以利用這個機會多設(shè)計一些師生互動和學生互動，來激發(fā)起學習的積極性，提高學習效率。同時我們可以利用這個單元不僅幫助學生掌握語言知識，培養(yǎng)語言能力，同時讓其了解新聞工作的重要性，培養(yǎng)起社會智能感。這個單元分為六個課時，它的教學目標是這樣的：語言目標是掌握詞匯表中的常用單詞和短語，掌握倒裝句的一些基本用法。 技能目標是能初步掌握約會的基本句型并在真實的場景下正確運用。新聞報道類文章的寫作技能。采訪的基本規(guī)范和溝通技能。情感目標是對新聞報道的客觀性和真實性有更好的理解。對新聞記者的職業(yè)有更深入的了解，并能體會其工作的重要性。下面我們來介紹一下第一課時的授課方式，第一課的教學目標是這樣的第一課時的教學目標語言目標:單詞：Occupation, journalist, editor, photographer, curious, personality, enthusiasm
人教版高中語文必修3《過秦論》說課稿3篇
本文篇幅較長，并且有一字句不易理解，因而對高一學生來說完全讀懂內(nèi)容有一些困難。這樣的話，老師就要做好引導工作，把一些難點，或是出現(xiàn)詞類活用比較多，局勢比較特殊的句子，老師可以先給學生畫出來，存疑，或是與同學們一起討論解決。對那些不易懂的字詞就引導學生聯(lián)系上下文提供的語境、前后涉及的情節(jié)加以推測、判斷，以培養(yǎng)學生依據(jù)文脈推斷詞義的好方法。要求學生點出重點實詞、框出通假字，主要是為幫助學生積累和掌握一些文言文中常見的一詞多義、異讀現(xiàn)象、古今異義和通假現(xiàn)象的詞語，并進一步得出規(guī)律，指導今后的文言文學習。詞類活用和特殊句式在文言文翻譯中難度較大，也是本文教學的兩大難點。要求學生標出有活用現(xiàn)象的字和劃出句式特殊的句子，是基于兩點考慮：1、積累一定數(shù)量的第一手例句；2、引導學生加以分類，找出每類的相同特征，并抽取出來形成規(guī)律性的東西，從而上升到理性認識，使學生能由學會一個到會學多個。翻譯過程中注重指導學生養(yǎng)成用符號法表示重點字句的好習慣，如點、框、圈、劃線等符號應約定一致，便于突出翻譯中的重點、難點及復習。我的提示著重歸納了實詞“制”“亡”“遺”“利”等，名詞活用、形容詞活用、使動用法，被動句、狀語后置句。
優(yōu)化營商環(huán)境服務中心民營經(jīng)濟服務工作總結(jié)（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(shè)、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(guān)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(guān)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(nèi)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(zhì)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(guān)“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(guān)于愛的方面師說：不錯，是關(guān)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(zhì)，讓學生關(guān)注時代、關(guān)注現(xiàn)實、關(guān)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(jié)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(guān)系，但要讓學生得出哲學是時代精神的總結(jié)和升華，還要聯(lián)系前面關(guān)于哲學的基礎(chǔ)知識進行總結(jié)歸納，因此可能會難以把握，另外關(guān)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(diào)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)學必修一對數(shù)函數(shù)的圖像和性質(zhì)教學設(shè)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(zhì)》 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(zhì)，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(zhì)；能利用對數(shù)函數(shù)的圖像與性質(zhì)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(zhì)，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(nèi)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(shè)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(shè)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(shè)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(cè)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(gòu)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(guān)，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(shè)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(guān)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(zhuǎn)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(zhuǎn)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(shè)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(zhì),如圓的性質(zhì)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(shè)——設(shè)所求圓的方程為(x-a)2+(y-b)2=r2;②列——由已知條件,建立關(guān)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(shè)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(shè)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(shè)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);
