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人教版高中生物必修2基因在染色體上說課稿
三、孟德爾遺傳規(guī)律的現(xiàn)代解釋①分離定律：在雜合體的細(xì)胞中，位于一對同源染色體上的等位基因，具有一定的獨(dú)立性；在減數(shù)分裂形成配子的過程中，等位基因隨同源染色體的分開而分離，獨(dú)立地隨配子遺傳給后代。②自由組合定律：位于非同源染色體上的非等位基因的分離或組合是互不干擾的；在減數(shù)分裂過程中，同源染色體的等位基因彼此分離的同時，非同源染色體上的非等位基因自由組合。總結(jié)：再次強(qiáng)調(diào)孟德爾遺傳定律的現(xiàn)代解釋課堂練習(xí)：書本31頁6、教學(xué)反思：本節(jié)課設(shè)置了一系列問題情境，層層設(shè)問，在學(xué)生答問、質(zhì)疑、討論過程中讓學(xué)生建構(gòu)新概念和新的知識體系，并通過教師及時掌握反饋信息，適時點(diǎn)撥、調(diào)節(jié)，讓學(xué)生在推理判斷中培養(yǎng)良好的思維習(xí)慣和對知識的遷移能力，而且通過留出一定的時間讓學(xué)生提問，體現(xiàn)了以學(xué)生為主體的思想。
人教版高中生物必修2染色體變異說課稿
四、說教學(xué)程序（一）.溫故知新、導(dǎo)入新課復(fù)習(xí)提問:基因突變導(dǎo)致生物變異的原因是什么?回答:基因突變是基因結(jié)構(gòu)發(fā)生改變，從而使遺傳信息改變，使蛋白質(zhì)結(jié)構(gòu)改變、生物性狀改變，即生物發(fā)生了變異。那么，基因是什么?它和染色體又有何關(guān)系?回答:基因是有遺傳效應(yīng)的DNA片斷，染色體是DNA的載體，基因在染色體上呈線形排列。引出新知:對于一個生物體來說，正常情況下，其染色體的結(jié)構(gòu)和數(shù)量都是穩(wěn)定的。但在自然條件或人為因素的影響下，染色體的結(jié)構(gòu)和數(shù)量均會發(fā)生改變，從而導(dǎo)致生物性狀的改變，這就屬于染色體變異。（二）.把握重點(diǎn)、突破難點(diǎn)重點(diǎn)的把握：1、染色體結(jié)構(gòu)的變異播放影片:貓叫綜合征幼兒。讓學(xué)生觀察: 患兒哭聲輕、音調(diào)高，很像貓叫。教師補(bǔ)充: 患兒的征狀---兩眼較低、耳位低下，存在著嚴(yán)重的智力障礙。闡述病因---染色體片段缺失
人教版高中英語必修1Journey Down the Mekong說課稿
2. let the Ss complete the forms paragraph by paragraph. Purpose here is to help Ss to get the habit of reading a passage as a whole, and pay attention to the organization of the text, as a result the Ss will fully understand the whole passage.3. ask Ss to retell the passage with the help of the key words in the form.Since the Ss in the class are in different levels, so I let them to fill in the blank to understand the meaning of the words and phrases better. ( That’s all for the while-reading. Now let’s move to the fifth step.)Step V: Post-reading (10mins) ---DiscussionIn this part students are asked to discuss in groups and list Wang Kun’s and Wang Wei’s attitudes about the trip. After that, Ss are encouraged to express their attitudes with the whole class. Collect their answers and don’t forget to praise them even if their answers may not be perfect.In this activity, discussion provides a vivid and active learning environment for Ss to communicate in English with newly learned language items. (Finally it comes to the homework.)StepⅥ: Homework (1min)1. Ss are required to read the text again after class and figure out the meaning of some complex sentences.2. Do the exercises on P19; This can help Ss to consolidate what they’ve learnt and make preparation for the next lessonPart4. Blackboard design.（說板書設(shè)計）On the top, there is the title of this lesson. On the left, there are main ideas for each paragraph. On the right, there are some new words and expressions.Unit 3 Travel journalJourney down the MekongMain idea of each para.:Para1: deciding to take a great bike trip along the Mekong river.Para2: Different attitudes between Wang kun and Wang wei.
人教版高中英語必修1Anne's best friend說課稿
Step 7 Language points 1．Vocabulary (1) go through (2) set down (3) a series of (4) on purpose (5) in order to (6)at dusk (7)entirely (8)face to face 2．Important sentences (1)…I’ve grown so crazy about everything to do with nature. (2)There was a time when … (3)I stayed awake on purpose until … (4)It was the first time … that I’d seen the night … (5)It’s no pleasure looking through … Purpose: 1．Master the required vocabulary and sentence structures. 2．Use them freely. Step 8 Consolidation 1．Find out the topic sentences 2．Retell the text according to the topic sentences Purpose: I want to know if my students understand the text. Step 9 Discussion Imagine you have to go into hiding like Anne and her family, what would you miss most? Giveyour reasons. Purpose: Train Ss’ oral English ability. Step 10 Homework Write an article on Friends. Purpose: 1． Improve the Ss’ writing ability. 2 Train the Ss’ ability of self—teaching and looking up information by themselves. Part 5 Blackboard design（說板書設(shè)計）Unit 1 Friendship Reading Anne’s Best Friend 1．Main idea of each paragraph: Para. 1 Anne made her diary her best friend. Para .2 Anne wrote her feelings in her diary. Para .3 Anne missed nature. Para.4 Anne saw the night face to face Para.5 Anne wanted to experience nature outdoors. 2．Listening: Exx.1 P3 3．Discussion: Exx.3 P3 Purpose: 1．Make Ss familiar with the passage 2．Make the design inductive, instructive and artistic.
人教版高中英語必修2Cultural Relics說課稿2篇
Ⅲ. Analysis of the teaching material:The topic of this unit is cultural relics. Students are quite interested in topics about different cultures around the world. This is the second period of the whole unit. As a reading class, the passage mainly talks about the history of the amber room (how it was made, sent as a gift, lost and rebuilt).According to the new national curriculum, when teaching reading, much emphasis should be put on training the students’ reading skills.Ⅳ. Teaching objectives1. Language objectives:1) Students are required to master the key words and phrases occurred in the passage (e.g. amazing, decorate, belong, in return, less than etc.)2) Students are required to learn the attributive clause and acquire the sentence pattern.2. 1) Students are required to describe a certain thing by using the new sentence patterns.2) Students are required to master two kinds of reading skills—skimming and scanning, and learn to use them in their daily reading.3. 1) Students are required to know the history of the amber room.2) Students are required to appreciate cultural relics and understand the importance of protecting them.Ⅴ. Teaching important and difficult points1) the new words, phrases, and sentence pattern in the course of reading.2) Teaching difficult point: Help the students master two kinds of reading skills—skimmingand scanning and learn to apply them in daily use.Ⅵ. Teaching methods:Task-based method & Top-down model Ⅶ. Teaching aids: PPT, pictures, blackboard Ⅷ. Teaching procedure:
人教版高中英語必修2The Olympic Games說課稿2篇
Purpose of my design:To ask the students to do these two tasks will make the Ss predict the story of this passage. As a result, it will deepen Ss’ memory of this story because they will have their own understanding of this story.Step 3. While-readingTask 1. (Individual work _____min)Skimming: ask students to skim the text and the main ideas of each paragraph in this passage. Please read it quickly and then match the sentences with the letters.Task 2. (Individual work _____min)Scanning: read the text quickly and decide the whether the following statements are true or false and give reasons.Task 3. (Pair work _____min)Listen to the tape and fill in the banks. Then read the paragraph with expression to your partner.Task4 (individual work min)Listen to the tape again and write down the main idea in one sentence.Purpose of my design: Enable students to understand the given material better by using different reading skills. And proper competition can arouse the Ss’ interest in English learning. “Task-based” teaching method is used here todevelop the Ss’ ability of communication and also their ability of co-operation will be well trainedStep 4. Post-readingTask 1. (Individual work, pair work, group work, class work; _____min)Discussion (group of 4):1. If you were Hippomenes, would you run against Atlanta?2. Do you think Hippomenes deserved to win the race? Why or why not?Step 5. HomeworkPlease read the story again carefully after class and imagine: What will happen during the race between Hippomenes and Atlanta? Who do you think will win the race? Do you think Atlanta would marry Hippomenes? Write an end for the story with thses questions.Purpose of my design: Homework is so important and necessary for to master the knowledge they learned after class. It will check whether the Ss achieve the teaching aims.Part 5 Blackboard design
人教版高中英語必修4Women of achievement說課稿4篇
Good morning, distinguished judges:It’s my honor to talk about my teaching ideas with you. Today my topic is Women of Achievement. My presentation consists of six parts: the analysis of teaching material and student, teaching aims, key and difficult points, teaching and studying method, teaching procedures and blackboard design.First, let’s focus on the analysis of teaching material. This lesson is from New Senior English for China Student’s Book 4 Unit 1, the reading part. The main topic of the passage is the introduction of a student of Africanwildlife. After this lesson, the students will learn more information about her studying chimps in Africa, and their reading and speaking abilities can be developed as well.The next part is the analysis of students. My students are in senior high students. They have learnt English for many years, they’ve known many words and sentences, but their speaking and reading abilities are still not very good. So I will practice their speaking and reading abilities through different exercises.According to the New Standard Curriculum and the present situation, I set the teaching aims as follows: firstly, knowledge aims. Students can grasp some new words, such as worthwhile, move off. Moreover, students can understand the content of the passage and get familiar with the topic of studying chimps in wildlife. Secondly, ability aims. Students can use reading strategies such as skimming and scanning in reading process. Thirdly, emotional aims. Students can have the awareness of protecting animals and care about animals.Based on the above analysis, the key point of this lesson is to get the main idea and the detailed information from the passage; the difficult point is to talk about the wildlife protection and use reading strategies.
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5Great scientists說課稿4篇
通過寫文章梗概，培養(yǎng)學(xué)生綜合運(yùn)用語言的能力，學(xué)習(xí)用恰當(dāng)?shù)挠⒄Z描述科學(xué)家的故事。這是本課的教學(xué)難點(diǎn)。教師可以使用完形填空的方式來幫助學(xué)生整理語篇，從而來降低難度。本課的教學(xué)重點(diǎn)的突破方法是：在閱讀前，讓學(xué)生初步了解得出科學(xué)觀點(diǎn)所需要的基本程序，從而輕松而自然地導(dǎo)入文章的閱讀；在閱讀過程中，由易到難設(shè)計快速閱讀和精讀的問題，層層推進(jìn)各種閱讀活動，讓學(xué)生對閱讀內(nèi)容從整體感知到細(xì)節(jié)理解，最后深層讀懂整篇文章，同時加強(qiáng)閱讀策略的指導(dǎo)，讓每個學(xué)生都主動參與課堂教學(xué)活動，最終達(dá)到提高閱讀能力的目的。Step 4 Post-readingGroup Activities四人小組共同合作，在老師的適當(dāng)指導(dǎo)下，就以下2個問題展開討論，讓學(xué)生就所知、所學(xué)、所感和所想融入話題，然后抽若干同學(xué)代表作小組發(fā)言。1. What do you think about John Snow, and what should we learn from him?2. Cholera was 19th century disease, which two diseases are similar to cholera today? Why?
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(yīng)該是學(xué)生比較感興趣的話題，學(xué)生往往對新聞工作充滿好奇，所以我們可以利用這個機(jī)會多設(shè)計一些師生互動和學(xué)生互動，來激發(fā)起學(xué)習(xí)的積極性，提高學(xué)習(xí)效率。同時我們可以利用這個單元不僅幫助學(xué)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(xué)目標(biāo)是這樣的：語言目標(biāo)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(biāo)是能初步掌握約會的基本句型并在真實(shí)的場景下正確運(yùn)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(biāo)是對新聞報道的客觀性和真實(shí)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(xué)目標(biāo)是這樣的第一課時的教學(xué)目標(biāo)語言目標(biāo):單詞：Occupation, journalist, editor, photographer, curious, personality, enthusiasm
人教版高中地理必修2綠色產(chǎn)品知多少說課稿
各小組派代表匯報。4、教師提出問題組織學(xué)生討論：⑴要想了解更多的綠色食品，了解綠色食品的銷售情況，我們應(yīng)該怎么做？⑵要想了解廣大消費(fèi)者對綠色食品的態(tài)度，食用綠色食品的意義，是否懂得辨認(rèn)綠色食品，以及什么樣的人群對此知識最缺乏等，我們應(yīng)該怎么做？組織學(xué)生匯報交流。5、做個“綠色食品”廣告設(shè)計師。為你喜歡的綠色食品設(shè)計廣告語，每組推薦一個。6、讓學(xué)生了解綠色食品認(rèn)證程序。7、綠色食品打“假”隊(duì)員在行動。8、向?qū)W生介紹生態(tài)綠色食品基地。三、活動總結(jié)：通過研究、探討，了解學(xué)生對綠色食品的態(tài)度。提問：民以食為天，吃，是一個大問題，如果你的爸爸媽媽讓你到超市買牛奶、方便面等，你會選擇什么樣的食品？為什么？希望通過今天的學(xué)習(xí)，同學(xué)們能夠做到綠色消費(fèi)，也希望你們向自己的家人、向周圍的了解學(xué)生對“無公害食品”、“有機(jī)食品”與“綠色食品”的認(rèn)識。
人教版高中地理必修2煤城焦作出路何在說課稿
分析過焦作市的地理概況和產(chǎn)業(yè)優(yōu)勢后，就需要針對由于資源枯竭所帶來的問題提出合理化的建議。既然是談經(jīng)濟(jì)轉(zhuǎn)型，就應(yīng)該將話題的范圍明確在這一領(lǐng)域內(nèi)。通過材料3的相關(guān)內(nèi)容，我們了解到焦作市需要在產(chǎn)業(yè)結(jié)構(gòu)調(diào)整、培育新的優(yōu)勢產(chǎn)業(yè)、增強(qiáng)綜合競爭力等三個整改方針上下功夫。因而引導(dǎo)學(xué)生針對優(yōu)勢與不足提出建議，以三個整改方針為基準(zhǔn)，衡量建議的可行性是鍛煉學(xué)生解決此類問題的有效途徑。在此我將教會學(xué)生的是解決問題方法而非案例的內(nèi)容，正所謂“授之以魚，不如授之以漁”。接下來針對學(xué)生的建議和教材資料分析所羅列的10點(diǎn)整改思路，由學(xué)生自由發(fā)言提出看法，通過教師的指導(dǎo)和學(xué)生的討論，進(jìn)而確定經(jīng)濟(jì)轉(zhuǎn)型建議的具體方案。最后注意將建議與產(chǎn)業(yè)優(yōu)勢相對照，看建議是否都是圍繞著產(chǎn)業(yè)優(yōu)勢而提出的，這樣做會加深學(xué)生的印象，通過建議和優(yōu)勢的對應(yīng)關(guān)系，將不難找出此類問題的解題思路。
人教版新課標(biāo)高中物理必修2功率說課稿2篇
（一）、復(fù)習(xí)提問1、請說出功的計算公式及功的單位2、我們用哪個物理量表示物體運(yùn)動的快慢？（二）、創(chuàng)設(shè)情景，引入新課1、播放多媒體素材，用起重機(jī)和一個工人搬運(yùn)幾百塊磚比較哪一種方法好？圖中的情景說明了什么問題?（教師通過所設(shè)計的情景，將學(xué)生引入怎樣比較做功快慢，讓學(xué)生發(fā)表自己的看法，初步知道物體做功是有快慢之分的。）（三）、進(jìn)行新課1、比較做功快慢的方法播放多媒體素材并提出問題：怎樣比較兩個人誰做功快誰做功慢？教師啟發(fā)：以前學(xué)習(xí)過要比較兩物體運(yùn)動的快慢，可以先確定路程再比較時間，也可以先確定時間再比較路程。在路程和時間都不同時，通過計算速度比較兩物體運(yùn)動的快慢。同理，要比較物體做功的快慢可采用什么方法？
人教版新課標(biāo)高中物理必修2功說課稿2篇
探究一：高中階段功的含義是什么？投影：初中九年級《物理》105頁學(xué)生思考：①圖中物體的勢能、動能分別如何變化？②物體能量的變化和做功是否存在關(guān)系？學(xué)生:分組討論，得出結(jié)論：如果物體的能量發(fā)生變化時，說明有力對物體做了功。教師:進(jìn)行點(diǎn)評和小結(jié)(設(shè)計意圖：對初中知識深化理論認(rèn)識，并為以后功能關(guān)系的教學(xué)作準(zhǔn)備)探究二：力對物體做功的兩個要素是什么？情景再現(xiàn)：找體重相對懸殊的兩位同學(xué)，①A同學(xué)試圖抱起B(yǎng)同學(xué)，但沒成功。②B同學(xué)抱起A同學(xué)在教室內(nèi)勻速走動。學(xué)生思考：在①中，A是否對B做功？在②中，B是否對A做功？學(xué)生:分析得出做功的兩要素：物體受到力的作用，并且在力的方向上發(fā)生位移.教師:讓學(xué)生分別例舉生活中力對物體做功和不做功的例子，（設(shè)計意圖：讓學(xué)生親身參與課堂實(shí)驗(yàn)，烘托課堂氣氛，相互協(xié)作增進(jìn)同學(xué)情誼）探究三：如果物體的位移不再力的方向上，那么力是否還對物體做功？
人教A版高中數(shù)學(xué)必修二圓柱、圓錐、圓臺和球的表面積與體積教學(xué)設(shè)計
1.圓柱、圓錐、圓臺的表面積與多面體的表面積一樣，圓柱、圓錐、圓臺的表面積也是圍成它的各個面的面積和。利用圓柱、圓錐、圓臺的展開圖如圖，可以得到它們的表面積公式：2.思考1：圓柱、圓錐、圓臺的表面積之間有什么關(guān)系？你能用圓柱、圓錐、圓臺的結(jié)構(gòu)特征來解釋這種關(guān)系嗎？3.練習(xí)一圓柱的一個底面積是S，側(cè)面展開圖是一個正方體，那么這個圓柱的側(cè)面積是（ ）A 4πS B 2πS C πS D 4.練習(xí)二：如圖所示，在邊長為4的正三角形ABC中，E，F(xiàn)分別是AB，AC的中點(diǎn)，D為BC的中點(diǎn)，H，G分別是BD，CD的中點(diǎn)，若將正三角形ABC繞AD旋轉(zhuǎn)180°，求陰影部分形成的幾何體的表面積．5. 圓柱、圓錐、圓臺的體積對于柱體、錐體、臺體的體積公式的認(rèn)識(1)等底、等高的兩個柱體的體積相同．(2)等底、等高的圓錐和圓柱的體積之間的關(guān)系可以通過實(shí)驗(yàn)得出，等底、等高的圓柱的體積是圓錐的體積的3倍．
人教版新課標(biāo)高中物理必修1勻變速直線運(yùn)動的位移與時間的關(guān)系說課稿2篇
培養(yǎng)學(xué)生合作交流意識和探究問題的能力，這一部分知識層層遞進(jìn)，符合學(xué)生由特殊到一般、由簡單到復(fù)雜的認(rèn)知規(guī)律。4、互動探究(1)極限思想的滲透讓學(xué)生閱讀“思考與討論”小版塊.培養(yǎng)學(xué)生的自學(xué)和閱讀能力提出下列問題，進(jìn)行分組討論：a、用課本上的方法估算位移，其結(jié)果比實(shí)際位移大還是??？為什么？b、為了提高估算的精確度，時間間隔小些好還是大些好？為什么？針對學(xué)生回答的多種可能性加以評價和進(jìn)一步指導(dǎo)。讓學(xué)生從討論的結(jié)果中歸納得出：△t越小，對位移的估算就越精確。滲透極限的思想。通過小組內(nèi)分工合作，討論交流，培養(yǎng)學(xué)生交流合作的精神，以及搜集信息、處理信息的能力；通過小組間對比總結(jié)，使學(xué)生學(xué)會在對比中發(fā)現(xiàn)問題，在解決問題過程中提高個人能力；
人教版新課標(biāo)高中物理必修1勻變速直線運(yùn)動的速度與時間的關(guān)系說課稿2篇
設(shè)計意圖：幾道例題及練習(xí)題，其中例1小車由靜止啟動開始行駛，以加速度 做勻加速運(yùn)動，求2s后的速度大?。窟M(jìn)而變式到：小車遇到紅燈剎車……，充分體現(xiàn)了“從生活到物理，從物理到社會”的物理教學(xué)理念；例題及練習(xí)題由淺入深、由易到難、各有側(cè)重，體現(xiàn)新課標(biāo)提出的讓不同的學(xué)生在物理上得到不同發(fā)展的教學(xué)理念。這一環(huán)節(jié)總的設(shè)計意圖是反饋教學(xué)，內(nèi)化知識。(6) 小結(jié)歸納，拓展深化我的理解是，小結(jié)歸納不應(yīng)該僅僅是知識的簡單羅列，而應(yīng)該是優(yōu)化認(rèn)知結(jié)構(gòu)，完善知識體系的一種有效手段，為充分發(fā)揮學(xué)生的主題作用，從學(xué)習(xí)的知識、方法、體驗(yàn)是那個方面進(jìn)行歸納，我設(shè)計了這么三個問題：① 通過本節(jié)課的學(xué)習(xí)，你學(xué)會了哪些知識；② 通過本節(jié)課的學(xué)習(xí)，你最大的體驗(yàn)是什么；③ 通過本節(jié)課的學(xué)習(xí)，你掌握了哪些學(xué)習(xí)物理的方法？
兩直線的交點(diǎn)坐標(biāo)教學(xué)設(shè)計人教A版高中數(shù)學(xué)選擇性必修第一冊
1.直線2x+y+8=0和直線x+y-1=0的交點(diǎn)坐標(biāo)是( )A.(-9,-10) B.(-9,10) C.(9,10) D.(9,-10)解析:解方程組{■(2x+y+8=0"," @x+y"-" 1=0"," )┤得{■(x="-" 9"," @y=10"," )┤即交點(diǎn)坐標(biāo)是(-9,10).答案:B 2.直線2x+3y-k=0和直線x-ky+12=0的交點(diǎn)在x軸上,則k的值為( )A.-24 B.24 C.6 D.± 6解析:∵直線2x+3y-k=0和直線x-ky+12=0的交點(diǎn)在x軸上,可設(shè)交點(diǎn)坐標(biāo)為(a,0),∴{■(2a"-" k=0"," @a+12=0"," )┤解得{■(a="-" 12"," @k="-" 24"," )┤故選A.答案:A 3.已知直線l1:ax+y-6=0與l2:x+(a-2)y+a-1=0相交于點(diǎn)P,若l1⊥l2,則點(diǎn)P的坐標(biāo)為 . 解析:∵直線l1:ax+y-6=0與l2:x+(a-2)y+a-1=0相交于點(diǎn)P,且l1⊥l2,∴a×1+1×(a-2)=0,解得a=1,聯(lián)立方程{■(x+y"-" 6=0"," @x"-" y=0"," )┤易得x=3,y=3,∴點(diǎn)P的坐標(biāo)為(3,3).答案:(3,3) 4.求證:不論m為何值,直線(m-1)x+(2m-1)y=m-5都通過一定點(diǎn). 證明:將原方程按m的降冪排列,整理得(x+2y-1)m-(x+y-5)=0,此式對于m的任意實(shí)數(shù)值都成立,根據(jù)恒等式的要求,m的一次項(xiàng)系數(shù)與常數(shù)項(xiàng)均等于零,故有{■(x+2y"-" 1=0"," @x+y"-" 5=0"," )┤解得{■(x=9"," @y="-" 4"." )┤
直線的點(diǎn)斜式方程教學(xué)設(shè)計人教A版高中數(shù)學(xué)選擇性必修第一冊
【答案】B [由直線方程知直線斜率為3，令x＝0可得在y軸上的截距為y＝－3.故選B.]3．已知直線l1過點(diǎn)P(2,1)且與直線l2：y＝x＋1垂直，則l1的點(diǎn)斜式方程為________．【答案】y－1＝－(x－2) [直線l2的斜率k2＝1，故l1的斜率為－1，所以l1的點(diǎn)斜式方程為y－1＝－(x－2)．]4．已知兩條直線y＝ax－2和y＝(2－a)x＋1互相平行，則a＝________. 【答案】1 [由題意得a＝2－a，解得a＝1.]5.無論k取何值,直線y-2=k(x+1)所過的定點(diǎn)是 . 【答案】(-1,2)6．直線l經(jīng)過點(diǎn)P(3,4)，它的傾斜角是直線y＝3x＋3的傾斜角的2倍，求直線l的點(diǎn)斜式方程．【答案】直線y＝3x＋3的斜率k＝3，則其傾斜角α＝60°，所以直線l的傾斜角為120°.以直線l的斜率為k′＝tan 120°＝－3.所以直線l的點(diǎn)斜式方程為y－4＝－3(x－3)．
