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人教版高中歷史必修3破解生命起源之謎說課稿2篇
過度：誠如牛頓所說 我之所以能夠取得今天的成就有很大原因是站在巨人的肩膀之上設問3：為什么這個時代選擇了達爾文來完成這一偉大的發(fā)現(xiàn)呢？（達爾文的個人努力）補充材料：（1831年起，他隨“貝格爾號”考察艦進行環(huán)球考察5年。考察結束后，在整理考察資料和實物標本的基礎上，經(jīng)過長期的研究，于1859年出版了《物種起源》一書，確立了生物的進化論說明達爾文的個人努力：學習、考察、學習、不迷信權威、勇于挑戰(zhàn)、不斷探索的精神，飽覽群書，挑戰(zhàn)和假設建立在大量的閱讀和觀察的基礎上，科學實證等等?？梢哉f達爾文身上有那個時代的一個濃縮的特征，當然他還有點運氣，不過，機遇永遠是為那些有準備的人提供的。）探究：達爾文“進化論”的影響思路引領：科學理論發(fā)展的影響可以從哪些方面分析？（經(jīng)濟、科學理論本身、人文學科、社會影響（對宗教，社會），對其他國家的影響）設問：達爾文進化論對1859年及以后的社會帶來了非常深遠的影響。有哪些影響呢？①挑戰(zhàn)封建神學的神創(chuàng)世，促進人類認識的飛躍
人教版高中生物必修2基因突變和基因重組說課稿
1、教材內(nèi)容本節(jié)是人教版普通高中標準實驗教科書生物必修2《遺傳與進化》的第五章《基因突變及其他變異》的第一節(jié)內(nèi)容。本節(jié)介紹了可遺傳變異的兩種類型：基因突變和基因重組，其中基因突變從實例對鐮刀型細胞貧血癥的分析入手，引入基因突變的概念，然后詳細闡述基因突變的原因和特點、意義。在闡述自然狀態(tài)下基因突變的頻率很低時，教材用實例說明在一個足夠大的群體中，即使基因突變頻率很低，突變個體仍然會占有一定的數(shù)量。這個實例體現(xiàn)了生物在進化過程中“變”與“不變”的平衡，有助于學生理解基因突變在生物進化中所占有的重要地位。在基因重組部分，教材設置了“思考與討論“的欄目，旨在讓學生利用數(shù)學方法，通過計算，體會基因重組機制提供的極其多樣的基因組合方式，從而幫助學生理解基因重組是生物多樣性形成的主要原因。正文中則簡要闡述了基因重組的概念、類型和意義。本節(jié)內(nèi)容引導學生從分子水平上理解遺傳物質如何引起生物變異的。
人教版高中生物必修2雜交育種與誘變育種說課稿
二、誘變育種1、創(chuàng)設情境，引出課題 出示教具或圖片：一穗具有黃粒性狀的玉米。問題：怎樣利用現(xiàn)有的玉米品種培育出具有黑色性狀的玉米新品種呢？2、閱讀資料、討論研究 課前布置興趣小組同學搜集有關航天誘變育種的資料，并在此基礎上進行整理。這樣可以培養(yǎng)學生搜集并且整理資料的能力，并體會科學技術與人們生產(chǎn)生活的密切聯(lián)系。 學生閱讀生物興趣小組課前搜集的有關航天誘變育種問題的資料及教材P100得內(nèi)容。以小組為單位討論回答有關誘變育種的有關問題，附：設置的問題：1、 新品種中有沒有產(chǎn)生新基因？2、空中誘發(fā)基因突變的條件有哪些？3、航天誘變育種有哪些優(yōu)點？4、地面上有哪些因素可以誘發(fā)生物體產(chǎn)生基因突變？5、誘變育種有哪些局限性？如何克服？以航天誘變育種為典型，解決誘變育種過程中遇到的相關問題。讓學生學會對已有知識進行應用。3、歸納總結，形成體系 通過以小組為單位的表達和交流，師生共同總結歸納，形成有關誘變育種的知識體系，提升學生對于知識的理解。
人教版高中政治必修3文化與經(jīng)濟、政治說課稿2篇
2、文化反作用經(jīng)濟政治師：經(jīng)濟政治決定文化，那么，文化不是被動消極的呢？生：思考回答：文化反作用經(jīng)濟政治，不同的文化對經(jīng)濟政治的影響不同。師：文化反作用經(jīng)濟政治，對社會發(fā)展有重要影響。文化反作用表現(xiàn)在，文化可以為經(jīng)濟政治的發(fā)展，對社會的發(fā)展，提供方向保證、智力支持和精神動力。（1）文化反作用的體現(xiàn)。師：現(xiàn)代民主國家中，世界民主的先驅是英國，但英國卻有國王，亞洲民主的先驅是日本，但日本卻有天皇，其一個重要原因是文化的影響。這說明什么？生：思考發(fā)言……師：不同民族的文化，影響不同民族和國家的歷史和發(fā)展道路。師：中東地區(qū)一直以來都是世界熱點地區(qū)，如巴以沖突、伊拉克戰(zhàn)爭、阿富汗戰(zhàn)爭、基地組織等，其一個重要原因是宗教文化的沖突。這說明什么？生：思考發(fā)言……師：不同文化的沖突，影響社會的和諧安定和世界的和平安寧。
人教版新課標高中物理必修2能量守恒定律與能源說課稿3篇
（3）內(nèi)陸和中西部城鎮(zhèn)主要以煤和火電為主；廣大農(nóng)村和邊遠地區(qū)大多正從使用農(nóng)作物秸稈等生物能源。（4）人均能源資源不足。我國是世界第三大能源生產(chǎn)國和第二大能源消費國，而我國能源短缺，特別是油氣資源短缺已成為制約我國經(jīng)濟發(fā)展的重要因素。相關數(shù)據(jù)——煤炭、石油和天然氣的人均資源占有量只有95t，世界平均值為209t，約是世界人均值的1/2；我國人均石油可采儲量3t，世界平均值為28t，約為世界平均值的1/10。我國人均能源消費量不足1.2噸標準煤，居世界89位，不足世界人均能源消費水平的一半，僅占發(fā)達國家的1/5～1/10。其中人均消費650kg標準煤，是世界平均額的95%；人均消費石油相當145kg標準煤，為世界平均數(shù)的16.8%；人均消費天然氣相當17.7kg標準煤，為世界平均數(shù)的3.9%；人均消費電力501.5kWh，為世界平均水平的25%。（5）是能源消費結構不合理，突出存在著一低兩高：即電能消費比例低，非商品生物能源消費量高，一次性商品能源消費中原煤消費比重高。原煤消費達到75%，遠高于26.2%的世界平均水平。
人教版新課標高中物理必修2動能和動能定理說課稿3篇
2、教學目標根據(jù)我對教材的理解、結合學生的實際情況、滲透新課程的教學理念，為提高全體學生的科學素養(yǎng)，按課程標準，以促進全體學生發(fā)展為目的。從知識與技能、過程與方法，情感態(tài)度與價值觀三個方向培養(yǎng)學生，擬定三個教學目標：知識與技能：（1）知道什么是動能。（2）正確理解和運用動能公式分析、解答有關問題。（3）掌握外力對物體所做的總功的計算，理解“代數(shù)和”的含義。（4）理解和運用動能定理。過程與方法：通過演繹推理過程，培養(yǎng)科學研究興趣，領略物理學中所蘊含的嚴謹?shù)倪壿嬯P系。情感、態(tài)度、價值觀：通過運用動能定理分析解決問題，感受成功的喜悅，培養(yǎng)學生對科學研究的興趣。3、教學的重點和難點重點：理解動能定理、應用動能定理解決力學問題。難點：應用動能定理解決多個過程的力學問題，以及變力做功或曲線運動中的動能定理運用。
人教版新課標高中物理必修2向心加速度說課稿
d．某物體沿直線向東運動，原來的速度是5m/s，2s后速度減小到3m/s，求2s內(nèi)物體速度變化。④如何探究物體作勻速圓周運動時，在Δt時間內(nèi)的速度變化？分析：有了同一直線上速度變化的鋪墊后，討論物體做勻速圓周運動速度的變化就比較自然了，為了給向心加速度方向的學習打好基礎，可以通過小組協(xié)作，進一步完成下列思考題，使同學們認識到：時間間隔起短，速度變化的方向起接近半徑方向。（多媒體屏幕投影）a．物體沿半徑為1m的軌道做勻速圓周運動，線速度大小為，求1s內(nèi)物體速度變化并畫出1s內(nèi)速度變化的示意圖。b．分別求出上題中物體在0.5s、0.25s內(nèi)速度變化并畫出相應的示意圖。由于沒有辦法直接利用實驗來驗證速度變化的方向，所以，我們采用提供思考題的方法，引導同學在合作學習、自主探究中完成。有了速度變化的研究為鋪墊，加速度的方向問題就迎刃而解了。
人教版高中政治必修4在實踐中追求和發(fā)展真理說課稿（二）
一、教學理論依據(jù)及設計理念以新課程理念和新課標為指針，依據(jù)建構主義理論、學科探究理論和多元智力理論，采用探究式的教學模式來組織實施本節(jié)課的教學。學生成為課堂的主體和知識的主動構建者。通過創(chuàng)設多種情境，讓學生積極參與、體驗、感悟，主動獲得新知，并逐步提高學生發(fā)現(xiàn)問題、分析問題和解決問題的能力。教師從課堂的主宰變?yōu)檎n堂的主導，是學生學習活動的組織者、引導者和合作者。教學過程是一個發(fā)散式的學生自主學習的過程。采用自主、合作、探究式的教學方式，讓學生有多元選擇，激發(fā)他們的潛能，發(fā)展他們的個性。二、教材分析1.教材的地位與作用：本框題是《生活與哲學》第二單元《探索世界與追求真理》第六課“求索真理的歷程”的第二節(jié)內(nèi)容。本單元的核心問題是如何看待我們周圍的世界，該問題也是《生活與哲學》整本書的核心問題之一。
人教版高中政治必修4認識運動把握規(guī)律說課稿（二）
歸納：第一句正確。承認運動的絕對性。第二句錯誤。否認相對靜止的存在。3.課堂小結，強化認識(2—3分鐘)課堂小結，可以把課堂傳授的知識盡快地轉化為學生的素質；簡單扼要的課堂小結，可使學生更深刻地理解政治理論在實際生活中的應用，并且逐漸地培養(yǎng)學生具有良好的個性。人類社會是物質世界長期發(fā)展的產(chǎn)物，世界的本質是物質，世界的真正統(tǒng)一性就在于它的物質性，物質又是運動的，運動的形式多種多樣，運動又是物質的運動，物質和運動是不可分割的，運動和靜止既有區(qū)別又有聯(lián)系，物質的運動是絕對的、無條件的和永恒的，而靜止是相對的、有條件的和暫時的。4.板書設計我比較注重直觀，系統(tǒng)的板書設計，還及時地體現(xiàn)教材中的知識點，以便于學生能夠理解掌握。
新人教版高中英語選修2Unit 2 Bridging Cultures-Discovering useful structures教學設計
The grammar of this unit is designed to review noun clauses. Sentences that use nouns in a sentence are called noun clauses. Nominal clauses can act as subject, object, predicate, appositive and other components in compound sentences. According to the above-mentioned different grammatical functions, nominal clauses are divided into subject clause, object clause, predicate clause and appositive clause. In this unit, we will review the three kinds of nominal clauses. Appositive clauses are not required to be mastered in the optional compulsory stage, so they are not involved.1. Guide the students to judge the compound sentences and determine the composition of the clauses in the sentence.2. Instruct students to try to learn grammar by generalizing grammar rules, controlling written practice, and semi-open oral output.3. Inspire the students to systematize the function and usage of noun clause1.Instruct students to try to learn grammar by generalizing grammar rules, controlling written practice, and semi-open oral output.2.Inspire the students to systematize the function and usage of noun clauseStep1: The teacher ask studetns to find out more nominal clauses from the reading passage and udnerline the nominal clauses.
新人教版高中英語選修2Unit 1 Science and Scientists-Learning about Language教學設計
Step 7: complete the discourse according to the grammar rules.Cholera used to be one of the most 1.__________ (fear) diseases in the world. In the early 19th century, _2_________ an outbreak of cholera hit Europe, millions of people died. But neither its cause, 3__________ its cure was understood. A British doctor, John Snow, wanted to solve the problem and he knew that cholera would not be controlled _4_________ its cause was found. In general, there were two contradictory theories 5 __________ explained how cholera spread. The first suggested that bad air caused the disease. The second was that cholera was caused by an _6_________(infect) from germs in food or water. John Snow thought that the second theory was correct but he needed proof. So when another outbreak of cholera hit London in 1854, he began to investigate. Later, with all the evidence he _7_________ (gather), John Snow was able to announce that the pump water carried cholera germs. Therefore, he had the handle of the pump _8_________ (remove) so that it couldn't be used. Through his intervention，the disease was stopped in its tracks. What is more, John Snow found that some companies sold water from the River Thames that __9__________________ (pollute) by raw waste. The people who drank this water were much more likely _10_________ (get) cholera than those who drank pure or boiled water. Through John Snow's efforts, the _11_________ (threaten) of cholera around the world saw a substantial increase. Keys： 1.feared 2.when 3. nor 4.unless 5.that/which 6.infection 7.had gathered 8.removed 9.was polluted 10.to get 11. threat
新人教版高中英語選修2Unit 1 Science and Scientists-Reading and thinking教學設計
Step 5： After learning the text, discuss with your peers about the following questions:1.John Snow believed Idea 2 was right. How did he finally prove it?2. Do you think John Snow would have solved this problem without the map?3. Cholera is a 19th century disease. What disease do you think is similar to cholera today?SARS and Covid-19 because they are both deadly and fatally infectious, have an unknown cause and need serious public health care to solve them urgently.keys:1. John Snow finally proved his idea because he found an outbreak that was clearly related to cholera, collected information and was able to tie cases outside the area to the polluted water.2. No. The map helped John Snow organize his ideas. He was able to identify those households that had had many deaths and check their water-drinking habits. He identified those houses that had had no deaths and surveyed their drinking habits. The evidence clearly pointed to the polluted water being the cause.3. SARS and Covid-19 because they are both deadly and fatally infectious, have an unknown cause and need serious public health care to solve them urgently.Step 6: Consolidate what you have learned by filling in the blanks:John Snow was a well-known _1___ in London in the _2__ century. He wanted to find the _3_____ of cholera in order to help people ___4_____ it. In 1854 when a cholera __5__ London, he began to gather information. He ___6__ on a map ___7___ all the dead people had lived and he found that many people who had ___8____ (drink) the dirty water from the __9____ died. So he decided that the polluted water ___10____ cholera. He suggested that the ___11__ of all water supplies should be _12______ and new methods of dealing with ____13___ water be found. Finally, “King Cholera” was __14_____.Keys: 1. doctor 2. 19th 3.cause 4.infected with 5.hit 6.marked 7.where 8.drunk 9.pump 10.carried 11.source 12.examined 13.polluted 14.defeatedHomework: Retell the text after class and preview its language points
新人教版高中英語選修2Unit 1 Science and Scientists-Discovering useful structures教學設計
The grammatical structure of this unit is predicative clause. Like object clause and subject clause, predicative clause is one of Nominal Clauses. The leading words of predicative clauses are that, what, how, what, where, as if, because, etc.The design of teaching activities aims to guide students to perceive the structural features of predicative clauses and think about their ideographic functions. Beyond that, students should be guided to use this grammar in the context apporpriately and flexibly.1. Enable the Ss to master the usage of the predicative clauses in this unit.2. Enable the Ss to use the predicative patterns flexibly.3. Train the Ss to apply some skills by doing the relevant exercises.1.Guide students to perceive the structural features of predicative clauses and think about their ideographic functions.2.Strengthen students' ability of using predicative clauses in context, but also cultivate their ability of text analysis and logical reasoning competence.Step1: Underline all the examples in the reading passage, where noun clauses are used as the predicative. Then state their meaning and functions.1) One theory was that bad air caused the disease.2) Another theory was that cholera was caused by an infection from germs in food or water.3) The truth was that the water from the Broad Street had been infected by waste.Sum up the rules of grammar:1. 以上黑體部分在句中作表語。2. 句1、2、3中的that在從句中不作成分，只起連接作用。 Step2: Review the basic components of predicative clauses1.Definition
新人教版高中英語選修2Unit 1 Science and Scientists-Using langauge教學設計
This happens because the dish soap molecules have a strong negative charge, and the milk molecules have a strong positive charge. Like magnets, these molecules are attracted to each other, and so they appear to move around on the plate, taking the food coloring with them, making it look like the colors are quickly moving to escape from the soap.Listening text:? Judy: Oh, I'm so sorry that you were ill and couldn't come with us on our field trip. How are you feeling now? Better?? Bill: Much better, thanks. But how was it?? Judy: Wonderful! I especially liked an area of the museum called Light Games.it was really cool. They had a hall of mirrors where I could see myself reflected thousands of times!? Bill: A hall of mirrors can be a lot of fun. What else did they have?? Judy: Well, they had an experiment where we looked at a blue screen for a while, and then suddenly we could see tiny bright lights moving around on it. You'll never guess what those bright lights were!? Bill: Come on, tell me!? Judy: They were our own blood cells. For some reason, our eyes play tricks on us when we look at a blue screen, and we can see our own blood cells moving around like little lights! But there was another thing I liked better. I stood in front of a white light, and it cast different shadows of me in every color of the rainbow!? Bill: Oh, I wish I had been there. Tell me more!? Judy: Well, they had another area for sound. They had a giant piano keyboard that you could use your feet to play. But then, instead of playing the sounds of a piano, it played the voices of classical singers! Then they had a giant dish, and when you spoke into it, it reflected the sound back and made it louder. You could use it to speak in a whisper to someone 17 meters away.? Bill: It all sounds so cool. I wish I could have gone with you? Judy: I know, but we can go together this weekend. I'd love to go there again!? Bill: That sounds like a great idea!
新人教版高中英語選修2Unit 3 Food and Culture-Discovering useful structures教學設計
The newspaper reported more than 100 people had been killed in the thunderstorm.報紙報道說有一百多人在暴風雨中喪生。(2)before、when、by the time、until、after、once等引導的時間狀語從句的謂語是一般過去時，以及by、before后面接過去的時間時，主句動作發(fā)生在從句的動作或過去的時間之前且表示被動時，要用過去完成時的被動語態(tài)。By the time my brother was 10, he had been sent to Italy.我弟弟10歲前就已經(jīng)被送到意大利了。Tons of rice had been produced by the end of last month. 到上月底已生產(chǎn)了好幾噸大米。(3) It was the first/second/last ... time that ...句中that引導的定語從句中，主語與謂語構成被動關系時，要用過去完成時的被動語態(tài)。It was the first time that I had seen the night fact to face in one and a half years. 這是我一年半以來第一次親眼目睹夜晚的景色。(4)在虛擬語氣中，條件句表示與過去事實相反，且主語與謂語構成被動關系時，要用過去完成時的被動語態(tài)。If I had been instructed by him earlier, I would have finished the task.如果我早一點得到他的指示，我早就完成這項任務了。If I had hurried, I wouldn't have missed the train.如果我快點的話，我就不會誤了火車。If you had been at the party, you would have met him. 如果你去了晚會，你就會見到他的。
新人教版高中英語選修2Unit 3 Food and Culture-Reading and thinking教學設計
The discourse explores the link between food and culture from a foreign’s perspective and it records some authentic Chinese food and illustrates the cultural meaning, gerography features and historic tradition that the food reflects. It is aimed to lead students to understand and think about the connection between food and culture. While teaching, the teacher should instruct students to find out the writing order and the writer’s experieces and feelings towards Chinese food and culture.1.Guide the students to read the text, sort out the information and dig out the topic.2.Understand the cultural connotation, regional characteristics and historical tradition of Chinese cuisine3.Understand and explore the relationship between food and people's personality4.Guide the students to use the cohesive words in the text5.Lead students to accurately grasp the real meaning of the information and improve the overall understanding ability by understanding the implied meaning behind the text.1. Enable the Ss to understand the structure and the writing style of the passage well.2. Lead the Ss to understand and think further about the connection between food and geography and local character traits.Step1: Prediction before reading. Before you read, look at the title, and the picture. What do you think this article is about?keys:It is about various culture and cuisine about a place or some countries.
新人教版高中英語選修2Unit 5 First Aid-Discovering useful structures教學設計
You have no excuse for not going.你沒有理由不去。He was punished for not having finished his homework.他因未完成作業(yè)而受到懲罰。2．動詞ing形式復合結構由物主代詞或人稱代詞賓格、名詞所有格或普通格加動詞ing，即“sb./sb.'s＋doing”構成。動詞ing形式的復合結構實際上是給動詞ing形式加了一個邏輯主語。動詞ing形式的復合結構有四種形式：①形容詞性物主代詞＋動詞ing②名詞所有格＋動詞ing③代詞賓格＋動詞ing④名詞＋動詞ingHer coming to help encouraged all of us.她來幫忙鼓舞了我們所有人。The baby was made awake by the door suddenly shutting.這個嬰兒被突然的關門聲吵醒了。Can you imagine him/Jack cooking at home?你能想象他/杰克在家做飯的樣子嗎？無生命名詞無論是作主語還是作賓語都不能用第②種形式。Tom's winning first prize last year impressed me a lot.湯姆去年得了一等獎使我印象深刻。Do you mind my/me/Jack's/Jack leaving now?你介意我/杰克現(xiàn)在離開嗎？Excuse me for my not coming on time．很抱歉我沒能按時來。His father's being ill made him worried.他父親病了，他很擔心。We are looking forward to the singer's/the singer to give us a concert.我們盼望著這位歌手來給我們舉辦一場演唱會。
小學美術桂美版三年級上冊《第15課實用美觀的竹器》教學設計說課稿
2學情分析本課內(nèi)容選用了苗族阿姐的背簍,黎族阿爸的魚籠,竹搖籃、簸箕等借助家庭中常見的竹器作為學習內(nèi)容,目的是要求學生用線描的方法對竹器的外形及竹編的篾紋進行描繪,鍛煉學生對事物的觀察能力和表現(xiàn)能力。在此之前學生已經(jīng)學過了如何用線描的方式描繪生活中的小物件,這為過渡到本課內(nèi)容的學習起到了鋪墊作用,同時為后面的素描教學內(nèi)容打下造型基礎。
小學美術桂美版三年級上冊《第10課漂亮的紙袋》教學設計說課稿
一．激趣導入?！ ?. 教師展示做好的漂亮紙袋，讓孩子們產(chǎn)生想要動手的愿望。 2.結合多媒體課件，出示漂亮紙袋?！ ⊥瑢W們，這些袋子漂亮嗎？你喜歡嗎？發(fā)現(xiàn)這些紙袋都是什么做成的？下面我們就來做一做這些漂亮的紙袋?！ 《畬W習制作紙袋的基本過程。 1.教師出示制作紙袋需要準備好的東西，讓孩子們自主檢查是否準備齊全?！ ?.多媒體出示紙袋制作步驟，讓學生注意觀察，清晰每一步制作的過程： ?。?）把長方形的對折，畫上虛線，用小剪刀剪去我們不需要的部分，然后用雙面膠粘貼，形成一個紙袋。
【高教版】中職數(shù)學基礎模塊上冊：3.3《函數(shù)的實際應用舉例》教學設計
課程分析中專數(shù)學課程教學是專業(yè)建設與專業(yè)課程體系改革的一部分，應與專業(yè)課教學融為一體，立足于為專業(yè)課服務，解決實際生活中常見問題，結合中專學生的實際，強調(diào)數(shù)學的應用性，以滿足學生在今后的工作崗位上的實際應用為主，這也體現(xiàn)了新課標中突出應用性的理念。分段函數(shù)的實際應用在本課程中的地位：（1） 函數(shù)是中專數(shù)學學習的重點和難點，函數(shù)的思想貫穿于整個中專數(shù)學之中，分段函數(shù)在科技和生活的各個領域有著十分廣泛的應用。（2） 本節(jié)所探討學習分段函數(shù)在生活生產(chǎn)中的實際問題上應用，培養(yǎng)學生分析與解決問題的能力，養(yǎng)成正確的數(shù)學化理性思維的同時，形成一種意識，即數(shù)學“源于生活、寓于生活、用于生活”。教材分析 教材使用的是中等職業(yè)教育課程改革國家規(guī)劃教材，依照13級教學計劃，函數(shù)的實際應用舉例內(nèi)容安排在第三章函數(shù)的最后一部分講解。本節(jié)內(nèi)容是在學生熟知函數(shù)的概念，表示方法和對函數(shù)性質有一定了解的基礎上研究分段函數(shù)，同時深化學生對函數(shù)概念的理解和認識，也為接下來學習指數(shù)函數(shù)和對數(shù)函數(shù)作了良好鋪墊。根據(jù)13級學生實際情況，由生活生產(chǎn)中的實際問題入手，求得分段函數(shù)此部分知識以學生生活常識為背景，可以引導學生分析得出。