(2) students are divided into groups according to the requirements of activity 3. Each student shares a story of personal experience or hearing-witnessing kindness, and then selects the most touching story in the group and shares it with the whole class. Before the students share the story, the teacher can instruct them to use the words and sentence patterns in the box to express. For example, the words in the box can be classified:Time order: first of all, then, after that, later, finally logical relationship :so, however, although, butTeachers can also appropriately add some transitional language to enrich students' expression:Afterwards, afterwards, at last, in the end, eventuallySpatial order: next to, far from, on the left, in front ofOtherwise, nevertheless, as a result, therefore, furthermore, in addition, as well asSummary: in a word, in short, on the whole, to sum up, in briefStep 8 Homework1. Understand the definition of "moral dilemma" and establish a correct moral view;2. Accumulate vocabulary about attitudes and emotions in listening texts and use them to express your own views;3. Complete relevant exercises in the guide plan.1、通過本節(jié)內(nèi)容學(xué)習(xí),學(xué)生能否理解理解“道德困境”的定義;2、通過本節(jié)內(nèi)容學(xué)習(xí),學(xué)生能否通過說話人所表達(dá)的內(nèi)容、說話的語氣、語調(diào)等來判斷其態(tài)度和情緒;3、通過本節(jié)內(nèi)容學(xué)習(xí),學(xué)生能否針對具體的道德困境發(fā)表自己的看法和見解,能否掌握聽力理訓(xùn)練中的聽力策略。
The price is the same as(the price was)before the war.價(jià)格與戰(zhàn)前相同。(4)定語從句中的“關(guān)系代詞+助動詞be”可以省略。The ticket(that/which was)booked by his sister has been sent to him.他妹妹訂的那張票已送到了他那里。Step 5 PracticeActivity 3(1) Guide students to complete the four activities in the Using Structures part of exercise book, in which activities 1 and 2 focus on ellipsis in dialogue answers, activity 3 focus on signs and headlines, two typical situations where ellipsis is used, and activity 4 focus on ellipsis in diary, an informal style.(2) Combine the examples in the above activities, ask students to summarize the omitted situations in groups, and make their own summary into a poster, and post it on the class wall after class to share with the class.(This step should give full play to the subjectivity of students, and teachers should encourage students to conclude different ellipsis phenomena according to their own understanding, they can conclude according to the different parts omitted in the sentence.)Step 6 Homework1. Understand and master the usages of ellipsis;2. Finish the other exercises in Using structures of Workbook.1、通過本節(jié)內(nèi)容學(xué)習(xí),學(xué)生是否理解和掌握省略的用法;2、通過本節(jié)內(nèi)容學(xué)習(xí),學(xué)生能否根據(jù)上下文語境或情景恢復(fù)句子中省略的成分,體會使用省略的效果;3、通過本節(jié)內(nèi)容學(xué)習(xí),學(xué)生能否獨(dú)立完成練習(xí)冊和導(dǎo)學(xué)案中的相關(guān)練習(xí)。
該板塊的活動主題是“介紹一個(gè)有顯著文化特征的地方”( Describe a place with distinctive cultural identity)。該板塊通過介紹中國城繼續(xù)聚焦中國文化。本單元主題圖呈現(xiàn)的是舊金山中國城的典型景象, Reading and Thinking部分也提到中國城,為該板塊作鋪墊。介紹中國城的目的主要是體現(xiàn)中國文化與美國多元文化的關(guān)系,它是美國多元文化的重要組成部分。中國城也是海外華人的精神家園和傳播中國文化的重要窗口,外國人在中國城能近距離體驗(yàn)中國文化。1. Read the text to understand the cultural characteristics of Chinatown in San Francisco and the relationship between Chinese culture and American multiculturalism;2. Through reading, learn to comb the main information of the article, understand the author's writing purpose and writing characteristics;3. Learn to give a comprehensive, accurate, and organized description of the city or town you live in;Learn to revise and evaluate your writing.Importance:1. Guide the students to read the introduction of Chinatown in San Francisco and grasp its writing characteristics;2. Guide students to introduce their city or town in a comprehensive, accurate and organized way;3. Learn to comb the main information of the article, understand the author's writing purpose, and master the core vocabulary.
Activity 81.Grasp the main idea of the listening.Listen to the tape and answer the following questions:Who are the two speakers in the listening? What is their relationship?What is the main idea of the first part of the listening? How about the second part?2.Complete the passage.Ask the students to quickly review the summaries of the two listening materials in activity 2. Then play the recording for the second time.Ask them to complete the passage and fill in the blanks.3.Play the recording again and ask the students to use the structure diagram to comb the information structure in the listening.(While listening, take notes. Capture key information quickly and accurately.)Step 8 Talking Activity 91.Focus on the listening text.Listen to the students and listen to the tape. Let them understand the attitudes of Wu Yue and Justin in the conversation.How does Wu Yue feel about Chinese minority cultures?What does Justin think of the Miao and Dong cultures?How do you know that?2.learn functional items that express concerns.Ask students to focus on the expressions listed in activity. 3.And try to analyze the meaning they convey, including praise (Super!).Agree (Exactly!)"(You're kidding.!)Tell me more about it. Tell me more about it.For example, "Yeah Sure." "Definitely!" "Certainly!" "No kidding!" "No wonder!" and so on.4.Ask the students to have conversations in small groups, acting as Jsim and his friends.Justin shares his travels in Guizhou with friends and his thoughts;Justin's friends should give appropriate feedback, express their interest in relevant information, and ask for information when necessary.In order to enrich the dialogue, teachers can expand and supplement the introduction of Miao, dong, Lusheng and Dong Dage.After the group practice, the teacher can choose several groups of students to show, and let the rest of the students listen carefully, after listening to the best performance of the group, and give at least two reasons.
1. We'll need ten months at least to have the restaurant decorated.2.Some traditional Chinese dishes from before the Ming Dynasty are still popular today.3.My grandpa's breakfast mainly includes whole grain biscuits and a glass of milk.4.People in this area would eat nearly a kilo of cheese per week.5. We enjoyed a special dinner in a fancy restaurant where the waiters all wore attractive suits.6. He prefers this brand of coffee which, as he said, has an unusually good flavor.Key:1. at a minimum 2. prior to3. consist of4. consume5. elegant6. exceptionalStep 5:Familiarize yourself with some food idioms by matching the meaning on the right with the colored words on the left.1.Public concern for the health of farm animals has mushroomed in the UK2.Anderson may be young but he's certainly rolling to doing dough!3.George is a popular lecturer. He often peppers his speech with jokes.4.As the person to bring home the bacon, he needs to find a stable job.5 He is often regarded as a ham actor for his over emphasized facial expressions. The media reported that these companies had treated pollution as a hot potato. 6.The media reported that these companies had treated pollution as a hot potato.7.Don't worry about the test tomorrow. It's going to be a piece of cake!8. It's best to fold the swimming ring when it is as flat as a pancake.A. completely flatB. something that is very easy to do C.an issue that is hard to deal withD.to include large numbers of somethingE.to earn on e's living to support a familyF. wealthyG.to rapidly increase in numberH. an actor who performs badly, especially by over emphasizing emotions
The activity theme of this section is to design various activities around the key words in the first text. Therefore, the activities require students to pay attention to the spelling of words. On the other hand, let students grasp the meaning of words more accurately through sentences and short texts. This kind of teaching design also helps to improve the ability of using English thinking.1. Cultivating students' ability to use word formation to induce and memorize vocabulary, and the ability to use lexical chunks to express meaning.2. Guide the students to think independently and use the correct form of words to complete sentences3. Cultivate students' habit of using lexical chunks to express language completely, guide students to draw words in sentences quickly, pay attention to word collocation, so as to accumulate more authentic expressions4. Instruct students to create sentences with the chunks.1. Enable students to use the language points in the real situation or specific contexts flexibly and appropriately.2. Guiding the Ss to use unit topic words and the sentence patterns in a richer context.Step1: Think of a word that best fits each definition.1. to remember sth2.to accept, admit, or recognize sth or the truth/existence of sth3. the process of changing sth or yourself to suit a new situation4 .to make sb feel less worried or unhappy5. a strong desire to achieve sth
Her tutor told her to acknowledge __________ other people had said if she cited their ideas, and advised her _______(read) lots of information in order to form __________wise opinion of her own.Now halfway __________ her exchange year, Xie Lei felt much more at home in the UK. She said __________ (engage) in British culture had helped and that she had been__________ (involve) in social activities. She also said while learning about business, she was acting as a cultural messenger __________(build) a bridge between the two countries. keys:Xie Lei, a 19yearold Chinese student, said goodbye to her family and friends in China and boarded (board) a plane for London six months ago in order to get a business qualification. She was ambitious(ambition) to set up a business after graduation. It was the first time that she had left (leave) home.At first, Xie Lei had to adapt to life in a different country. She chose to live with a host family, who can help with her adaptation (adapt) to the new culture. When she missed home, she felt comforted (comfort) to have a second family. Also Xie Lei had to satisfy academic requirements. Her tutor told her to acknowledge what other people had said if she cited their ideas, and advised her to read lots of information in order to form a wise opinion of her own.Now halfway through her exchange year, Xie Lei felt much more at home in the UK. She said engaging (engage) in British culture had helped and that she had been involved (involve) in social activities. She also said while learning about business, she was acting as a cultural messenger building a bridge between the two countries.
The theme of this section is to express people's views on studying abroad. With the continuous development of Chinese economic construction, especially the general improvement of people's living standards, the number of Chinese students studying abroad at their own expense is on the rise. Many students and parents turn their attention to the world and regard studying abroad as an effective way to improve their quality, broaden their horizons and master the world's advanced scientific knowledge, which is very important for the fever of going abroad. Studying abroad is also an important decision made by a family for their children. Therefore, it is of great social significance to discuss this issue. The theme of this section is the column discussion in the newspaper: the advantages and disadvantages of studying abroad. The discourse is about two parents' contribution letters on this issue. They respectively express their own positions. One thinks that the disadvantages outweigh the advantages, and the other thinks that the advantages outweigh the disadvantages. The two parents' arguments are well founded and logical. It is worth noting that the two authors do not express their views on studying abroad from an individual point of view, but from a national or even global point of view. These two articles have the characteristics of both letters and argumentative essays1.Guide the students to read these two articles, and understand the author's point of view and argument ideas2.Help the students to summarize the structure and writing methods of argumentative writing, and guides students to correctly understand the advantages and disadvantages of studying abroad3.Cultivate students' ability to analyze problems objectively, comprehensively and deeply
1. How is Hunan cuisine somewhat different from Sichuan cuisine?The heat in Sichuan cuisine comes from chilies and Sichuan peppercorns. Human cuisine is often hotter and the heat comes from just chilies.2.What are the reasons why Hunan people like spicy food?Because they are a bold people. But many Chinese people think that hot food helps them overcome the effects of rainy or wet weather.3.Why do so many people love steamed fish head covered with chilies?People love it because the meat is quite tender and there are very few small bones.4.Why does Tingting recommend bridge tofu instead of dry pot duck with golden buns?Because bridge tofu has a lighter taste.5 .Why is red braised pork the most famous dish?Because Chairman Mao was from Hunan, and this was his favorite food.Step 5: Instruct students to make a short presentation to the class about your choice. Use the example and useful phrases below to help them.? In groups of three, discuss what types of restaurant you would like to take a foreign visitor to, and why. Then take turns role-playing taking your foreign guest to the restaurant you have chosen. One of you should act as the foreign guest, one as the Chinese host, and one as the waiter or waitress. You may start like this:? EXAMPLE? A: I really love spicy food, so what dish would you recommend?? B: I suggest Mapo tofu.? A: Really ? what's that?
假定你是英國的Jack,打算來中國旅行,請你給你的中國筆友李華寫一封信,要點(diǎn)如下:1.你的旅行計(jì)劃:北京→泰山→杭州;2.征求建議并詢問他是否愿意充當(dāng)你的導(dǎo)游。注意:1.詞數(shù)80左右(開頭和結(jié)尾已給出,不計(jì)入總詞數(shù));2.可以適當(dāng)增加細(xì)節(jié),以使行文連貫。參考詞匯:故宮 the Forbidden City;泰山 Mount TaiDear Li Hua,I'm glad to tell you that 'm going to visit China.First,I am planning to visit Beijing,the capitalof China,where I am looking forward to enjoying the Great Wall,the Forbidden City and somebeautiful parks.Then I intend to go to visit Mount Tai in Shandong Province.I've heard that it is one ofthe most famous mountains in China and I can't wait to enjoy the amazing sunrise there.After that,I amalso going to Hangzhou.It is said that it is a beautiful modern city with breathtaking natural sights,among which the West Lake is a well- known tourist attraction.What do you think of my travel plan? Will you act as my guide? Hope to hear from you soon.
The theme of this activity is to learn the first aid knowledge of burns. Burns is common in life, but there are some misunderstandings in manual treatment. This activity provides students with correct first aid methods, so as not to take them for granted in an emergency. This section guides students to analyze the causes of scald and help students avoid such things. From the perspective of text structure and collaborative features, the text is expository. Expository, with explanation as the main way of expression, transmits knowledge and information to readers by analyzing concepts and elaborating examples. This text arranges the information in logical order, clearly presents three parts of the content through the subtitle, accurately describes the causes, types, characteristics and first aid measures of burns, and some paragraphs use topic sentences to summarize the main idea, and the level is very clear.1. Guide students to understand the causes, types, characteristics and first aid methods of burns, through reading2. Enhance students’ ability to deal withburnss and their awareness of burns prevention3. Enable students to improve the ability to judge the types of texts accurately and to master the characteristics and writing techniques of expository texts.Guide students to understand the causes, types, characteristics and first aid methods of burns, through readingStep1: Lead in by discussing the related topic:1. What first-aid techniques do you know of ?CPR; mouth to mouth artificial respiration; the Heimlich Manoeuvre
探究新知問題1:已知100件產(chǎn)品中有8件次品,現(xiàn)從中采用有放回方式隨機(jī)抽取4件.設(shè)抽取的4件產(chǎn)品中次品數(shù)為X,求隨機(jī)變量X的分布列.(1):采用有放回抽樣,隨機(jī)變量X服從二項(xiàng)分布嗎?采用有放回抽樣,則每次抽到次品的概率為0.08,且各次抽樣的結(jié)果相互獨(dú)立,此時(shí)X服從二項(xiàng)分布,即X~B(4,0.08).(2):如果采用不放回抽樣,抽取的4件產(chǎn)品中次品數(shù)X服從二項(xiàng)分布嗎?若不服從,那么X的分布列是什么?不服從,根據(jù)古典概型求X的分布列.解:從100件產(chǎn)品中任取4件有 C_100^4 種不同的取法,從100件產(chǎn)品中任取4件,次品數(shù)X可能取0,1,2,3,4.恰有k件次品的取法有C_8^k C_92^(4-k)種.一般地,假設(shè)一批產(chǎn)品共有N件,其中有M件次品.從N件產(chǎn)品中隨機(jī)抽取n件(不放回),用X表示抽取的n件產(chǎn)品中的次品數(shù),則X的分布列為P(X=k)=CkM Cn-kN-M CnN ,k=m,m+1,m+2,…,r.其中n,N,M∈N*,M≤N,n≤N,m=max{0,n-N+M},r=min{n,M},則稱隨機(jī)變量X服從超幾何分布.
二項(xiàng)式定理形式上的特點(diǎn)(1)二項(xiàng)展開式有n+1項(xiàng),而不是n項(xiàng).(2)二項(xiàng)式系數(shù)都是C_n^k(k=0,1,2,…,n),它與二項(xiàng)展開式中某一項(xiàng)的系數(shù)不一定相等.(3)二項(xiàng)展開式中的二項(xiàng)式系數(shù)的和等于2n,即C_n^0+C_n^1+C_n^2+…+C_n^n=2n.(4)在排列方式上,按照字母a的降冪排列,從第一項(xiàng)起,次數(shù)由n次逐項(xiàng)減少1次直到0次,同時(shí)字母b按升冪排列,次數(shù)由0次逐項(xiàng)增加1次直到n次.1.判斷(正確的打“√”,錯(cuò)誤的打“×”)(1)(a+b)n展開式中共有n項(xiàng). ( )(2)在公式中,交換a,b的順序?qū)Ω黜?xiàng)沒有影響. ( )(3)Cknan-kbk是(a+b)n展開式中的第k項(xiàng). ( )(4)(a-b)n與(a+b)n的二項(xiàng)式展開式的二項(xiàng)式系數(shù)相同. ( )[解析] (1)× 因?yàn)?a+b)n展開式中共有n+1項(xiàng).(2)× 因?yàn)槎?xiàng)式的第k+1項(xiàng)Cknan-kbk和(b+a)n的展開式的第k+1項(xiàng)Cknbn-kak是不同的,其中的a,b是不能隨便交換的.(3)× 因?yàn)镃knan-kbk是(a+b)n展開式中的第k+1項(xiàng).(4)√ 因?yàn)?a-b)n與(a+b)n的二項(xiàng)式展開式的二項(xiàng)式系數(shù)都是Crn.[答案] (1)× (2)× (3)× (4)√
(2)方法一:第一次取到一件不合格品,還剩下99件產(chǎn)品,其中有4件不合格品,95件合格品,于是第二次又取到不合格品的概率為4/99,由于這是一個(gè)條件概率,所以P(B|A)=4/99.方法二:根據(jù)條件概率的定義,先求出事件A,B同時(shí)發(fā)生的概率P(AB)=(C_5^2)/(C_100^2 )=1/495,所以P(B|A)=(P"(" AB")" )/(P"(" A")" )=(1/495)/(5/100)=4/99.6.在某次考試中,要從20道題中隨機(jī)地抽出6道題,若考生至少答對其中的4道題即可通過;若至少答對其中5道題就獲得優(yōu)秀.已知某考生能答對其中10道題,并且知道他在這次考試中已經(jīng)通過,求他獲得優(yōu)秀成績的概率.解:設(shè)事件A為“該考生6道題全答對”,事件B為“該考生答對了其中5道題而另一道答錯(cuò)”,事件C為“該考生答對了其中4道題而另2道題答錯(cuò)”,事件D為“該考生在這次考試中通過”,事件E為“該考生在這次考試中獲得優(yōu)秀”,則A,B,C兩兩互斥,且D=A∪B∪C,E=A∪B,由古典概型的概率公式及加法公式可知P(D)=P(A∪B∪C)=P(A)+P(B)+P(C)=(C_10^6)/(C_20^6 )+(C_10^5 C_10^1)/(C_20^6 )+(C_10^4 C_10^2)/(C_20^6 )=(12" " 180)/(C_20^6 ),P(E|D)=P(A∪B|D)=P(A|D)+P(B|D)=(P"(" A")" )/(P"(" D")" )+(P"(" B")" )/(P"(" D")" )=(210/(C_20^6 ))/((12" " 180)/(C_20^6 ))+((2" " 520)/(C_20^6 ))/((12" " 180)/(C_20^6 ))=13/58,即所求概率為13/58.
解析:因?yàn)闇p法和除法運(yùn)算中交換兩個(gè)數(shù)的位置對計(jì)算結(jié)果有影響,所以屬于組合的有2個(gè).答案:B2.若A_n^2=3C_(n"-" 1)^2,則n的值為( )A.4 B.5 C.6 D.7 解析:因?yàn)锳_n^2=3C_(n"-" 1)^2,所以n(n-1)=(3"(" n"-" 1")(" n"-" 2")" )/2,解得n=6.故選C.答案:C 3.若集合A={a1,a2,a3,a4,a5},則集合A的子集中含有4個(gè)元素的子集共有 個(gè). 解析:滿足要求的子集中含有4個(gè)元素,由集合中元素的無序性,知其子集個(gè)數(shù)為C_5^4=5.答案:54.平面內(nèi)有12個(gè)點(diǎn),其中有4個(gè)點(diǎn)共線,此外再無任何3點(diǎn)共線,以這些點(diǎn)為頂點(diǎn),可得多少個(gè)不同的三角形?解:(方法一)我們把從共線的4個(gè)點(diǎn)中取點(diǎn)的多少作為分類的標(biāo)準(zhǔn):第1類,共線的4個(gè)點(diǎn)中有2個(gè)點(diǎn)作為三角形的頂點(diǎn),共有C_4^2·C_8^1=48(個(gè))不同的三角形;第2類,共線的4個(gè)點(diǎn)中有1個(gè)點(diǎn)作為三角形的頂點(diǎn),共有C_4^1·C_8^2=112(個(gè))不同的三角形;第3類,共線的4個(gè)點(diǎn)中沒有點(diǎn)作為三角形的頂點(diǎn),共有C_8^3=56(個(gè))不同的三角形.由分類加法計(jì)數(shù)原理,不同的三角形共有48+112+56=216(個(gè)).(方法二 間接法)C_12^3-C_4^3=220-4=216(個(gè)).
《奇偶性》內(nèi)容選自人教版A版第一冊第三章第三節(jié)第二課時(shí);函數(shù)奇偶性是研究函數(shù)的一個(gè)重要策略,因此奇偶性成為函數(shù)的重要性質(zhì)之一,它的研究也為今后指對函數(shù)、冪函數(shù)、三角函數(shù)的性質(zhì)等后續(xù)內(nèi)容的深入起著鋪墊的作用.課程目標(biāo)1、理解函數(shù)的奇偶性及其幾何意義;2、學(xué)會運(yùn)用函數(shù)圖象理解和研究函數(shù)的性質(zhì);3、學(xué)會判斷函數(shù)的奇偶性.?dāng)?shù)學(xué)學(xué)科素養(yǎng)1.數(shù)學(xué)抽象:用數(shù)學(xué)語言表示函數(shù)奇偶性;2.邏輯推理:證明函數(shù)奇偶性;3.數(shù)學(xué)運(yùn)算:運(yùn)用函數(shù)奇偶性求參數(shù);4.數(shù)據(jù)分析:利用圖像求奇偶函數(shù);5.數(shù)學(xué)建模:在具體問題情境中,運(yùn)用數(shù)形結(jié)合思想,利用奇偶性解決實(shí)際問題。重點(diǎn):函數(shù)奇偶性概念的形成和函數(shù)奇偶性的判斷;難點(diǎn):函數(shù)奇偶性概念的探究與理解.教學(xué)方法:以學(xué)生為主體,采用誘思探究式教學(xué),精講多練。
一、復(fù)習(xí)回顧,溫故知新1. 任意角三角函數(shù)的定義【答案】設(shè)角 它的終邊與單位圓交于點(diǎn) 。那么(1) (2) 2.誘導(dǎo)公式一 ,其中, 。終邊相同的角的同一三角函數(shù)值相等二、探索新知思考1:(1).終邊相同的角的同一三角函數(shù)值有什么關(guān)系?【答案】相等(2).角 -α與α的終邊 有何位置關(guān)系?【答案】終邊關(guān)于x軸對稱(3).角 與α的終邊 有何位置關(guān)系?【答案】終邊關(guān)于y軸對稱(4).角 與α的終邊 有何位置關(guān)系?【答案】終邊關(guān)于原點(diǎn)對稱思考2: 已知任意角α的終邊與單位圓相交于點(diǎn)P(x, y),請同學(xué)們思考回答點(diǎn)P關(guān)于原點(diǎn)、x軸、y軸對稱的三個(gè)點(diǎn)的坐標(biāo)是什么?【答案】點(diǎn)P(x, y)關(guān)于原點(diǎn)對稱點(diǎn)P1(-x, -y)點(diǎn)P(x, y)關(guān)于x軸對稱點(diǎn)P2(x, -y) 點(diǎn)P(x, y)關(guān)于y軸對稱點(diǎn)P3(-x, y)
冪函數(shù)是在繼一次函數(shù)、反比例函數(shù)、二次函數(shù)之后,又學(xué)習(xí)了單調(diào)性、最值、奇偶性的基礎(chǔ)上,借助實(shí)例,總結(jié)出冪函數(shù)的概念,再借助圖像研究冪函數(shù)的性質(zhì).課程目標(biāo)1、理解冪函數(shù)的概念,會畫冪函數(shù)y=x,y=x2,y=x3,y=x-1,y=x 的圖象;2、結(jié)合這幾個(gè)冪函數(shù)的圖象,理解冪函數(shù)圖象的變化情況和性質(zhì);3、通過觀察、總結(jié)冪函數(shù)的性質(zhì),培養(yǎng)學(xué)生概括抽象和識圖能力.?dāng)?shù)學(xué)學(xué)科素養(yǎng)1.數(shù)學(xué)抽象:用數(shù)學(xué)語言表示函數(shù)冪函數(shù);2.邏輯推理:常見冪函數(shù)的性質(zhì);3.數(shù)學(xué)運(yùn)算:利用冪函數(shù)的概念求參數(shù);4.數(shù)據(jù)分析:比較冪函數(shù)大?。?.數(shù)學(xué)建模:在具體問題情境中,運(yùn)用數(shù)形結(jié)合思想,利用冪函數(shù)性質(zhì)、圖像特點(diǎn)解決實(shí)際問題。重點(diǎn):常見冪函數(shù)的概念、圖象和性質(zhì);難點(diǎn):冪函數(shù)的單調(diào)性及比較兩個(gè)冪值的大?。?/p>
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4.3.2節(jié)《對數(shù)的運(yùn)算》。其核心是弄清楚對數(shù)的定義,掌握對數(shù)的運(yùn)算性質(zhì),理解它的關(guān)鍵就是通過實(shí)例使學(xué)生認(rèn)識對數(shù)式與指數(shù)式的關(guān)系,分析得出對數(shù)的概念及對數(shù)式與指數(shù)式的 互化,通過實(shí)例推導(dǎo)對數(shù)的運(yùn)算性質(zhì)。由于它還與后續(xù)很多內(nèi)容,比如對數(shù)函數(shù)及其性質(zhì),這也是高考必考內(nèi)容之一,所以在本學(xué)科有著很重要的地位。解決重點(diǎn)的關(guān)鍵是抓住對數(shù)的概念、并讓學(xué)生掌握對數(shù)式與指數(shù)式的互化;通過實(shí)例推導(dǎo)對數(shù)的運(yùn)算性質(zhì),讓學(xué)生準(zhǔn)確地運(yùn)用對數(shù)運(yùn)算性質(zhì)進(jìn)行運(yùn)算,學(xué)會運(yùn)用換底公式。培養(yǎng)學(xué)生數(shù)學(xué)運(yùn)算、數(shù)學(xué)抽象、邏輯推理和數(shù)學(xué)建模的核心素養(yǎng)。1、理解對數(shù)的概念,能進(jìn)行指數(shù)式與對數(shù)式的互化;2、了解常用對數(shù)與自然對數(shù)的意義,理解對數(shù)恒等式并能運(yùn)用于有關(guān)對數(shù)計(jì)算。
學(xué)生已經(jīng)學(xué)習(xí)了指數(shù)運(yùn)算性質(zhì),有了這些知識作儲備,教科書通過利用指數(shù)運(yùn)算性質(zhì),推導(dǎo)對數(shù)的運(yùn)算性質(zhì),再學(xué)習(xí)利用對數(shù)的運(yùn)算性質(zhì)化簡求值。課程目標(biāo)1、通過具體實(shí)例引入,推導(dǎo)對數(shù)的運(yùn)算性質(zhì);2、熟練掌握對數(shù)的運(yùn)算性質(zhì),學(xué)會化簡,計(jì)算.數(shù)學(xué)學(xué)科素養(yǎng)1.數(shù)學(xué)抽象:對數(shù)的運(yùn)算性質(zhì);2.邏輯推理:換底公式的推導(dǎo);3.數(shù)學(xué)運(yùn)算:對數(shù)運(yùn)算性質(zhì)的應(yīng)用;4.數(shù)學(xué)建模:在熟悉的實(shí)際情景中,模仿學(xué)過的數(shù)學(xué)建模過程解決問題.重點(diǎn):對數(shù)的運(yùn)算性質(zhì),換底公式,對數(shù)恒等式及其應(yīng)用;難點(diǎn):正確使用對數(shù)的運(yùn)算性質(zhì)和換底公式.教學(xué)方法:以學(xué)生為主體,采用誘思探究式教學(xué),精講多練。教學(xué)工具:多媒體。一、 情景導(dǎo)入回顧指數(shù)性質(zhì):(1)aras=ar+s(a>0,r,s∈Q).(2)(ar)s= (a>0,r,s∈Q).(3)(ab)r= (a>0,b>0,r∈Q).那么對數(shù)有哪些性質(zhì)?如 要求:讓學(xué)生自由發(fā)言,教師不做判斷。而是引導(dǎo)學(xué)生進(jìn)一步觀察.研探.