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新人教版高中英語選修2Unit 2 Reading for writing教學設計
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
新人教版高中英語選修2Unit 2 Learning about Language教學設計
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
新人教版高中英語選修2Unit 5 Reading for writing教學設計
你校英語報計劃出版一期急救常識?？?現(xiàn)面向全校學生公開征集稿件,你有意參加。請你根據(jù)下面提示內(nèi)容,用英語寫一篇短文,介紹在車禍現(xiàn)場對傷者進行急救的方法和步驟。1.確?，F(xiàn)場的安全;2.詢問傷者,確保其呼吸正常;3.檢查傷口,如流血則應采取止血措施;4.如需急救,確保其處于康復位置。注意:1.詞數(shù)80左右;2.可以適當增加細節(jié),以使行文連貫。參考詞匯:康復位置 recovery positionAs we all know, having a knowledge of first aid can make a great difference in our daily life. If a traffic accident happens and someone is injured, the following steps can be used to treat the injured.In the first place, we should make sure that the accident scene is safe so that we won’t get hurt. We should ask the injured person if he is OK, and see if he is breathing. What’s more, we should check for cuts and wounds. If he is bleeding badly, it is vital that we should try to stop the bleeding by applying pressure to the injury. This is because if a person loses too much blood, he may die. If necessary, take the injured person to the hospital as soon as possible.Do remember: when giving first aid, please be sure to place the person in a recovery position.
新人教版高中英語選修2Unit 2 Reading and thinking教學設計
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.
新人教版高中英語選修2Unit 2 Using langauge-Listening教學設計
? B: Absolutely! Getting involved with Chinese cultural activities there definitely helped a lot. I got to practice my Chinese on a daily basis, and I could learn how native Chinese speakers spoke.? A: What do you feel is your biggest achievement?? B: Learning Chinese characters! I have learnt about 1,500 so far. When I first started, I didn't think it was even going to be possible to learn so many, but now I find that I can read signs, menus, and even some easy newspaper articles.? A: What are you most keen on?? B: I've really become keen on learning more about the Chinese culture, in particular Chinese calligraphy. As I have learnt Chinese characters, I have developed a great appreciation for their meaning. I want to explore Chinese characters by learning how to write them in a more beautiful way. ? A: Finally, what do you want to say to anyone interested in learning Chinese?? I have really become keen on learning more about the Chinese culture, in particular Chinese Calligraphy. As I have learnt Chinese character, I have developed a great appreciation for their meaning. I want to explore Chinese characters by learning how to write them in a more beautiful way.? A: Finally, what do you want to say to anyone interested in learning Chinese?? B: I'd say, give it a shot! While some aspects may be difficult, it is quite rewarding and you will be happy that you tried.? A: Thanks for your time. ? B:You're welcome.
新人教版高中英語選修2Unit 5 Learning about Language教學設計
The purpose of this section of vocabulary exercises is to consolidate the key words in the first part of the reading text, let the students write the words according to the English definition, and focus on the detection of the meaning and spelling of the new words. The teaching design includes use English definition to explain words, which is conducive to improving students' interest in vocabulary learning, cultivating their sense of English language and thinking in English, and making students willing to use this method to better grasp the meaning of words, expand their vocabulary, and improve their ability of vocabulary application. Besides, the design offers more context including sentences and short passage for students to practice words flexibly.1. Guide students to understand and consolidate the meaning and usage of the vocabulary in the context, 2. Guide the students to use the unit topic vocabulary in a richer context3. Let the students sort out and accumulate the accumulated vocabulary, establishes the semantic connection between the vocabulary,4. Enable students to understand and master the vocabulary more effectivelyGuiding the Ss to use unit topic words and the sentence patterns in a richer context.Step1: Read the passage about chemical burns and fill in the blanks with the correct forms of the words in the box.
新人教版高中英語選修2Unit 5 Reading and thinking教學設計
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
新人教版高中英語選修2Unit 5 Using langauge-Listening教學設計
The theme of this section is to learn how to make emergency calls. Students should learn how to make emergency calls not only in China, but also in foreign countries in English, so that they can be prepared for future situations outside the home.The emergency telephone number is a vital hotline, which should be the most clear, rapid and effective communication with the acute operator.This section helps students to understand the emergency calls in some countries and the precautions for making emergency calls. Through the study of this section, students can accumulate common expressions and sentence patterns in this context. 1.Help students accumulate emergency telephone numbers in different countries and learn more about first aid2.Guide the students to understand the contents and instructions of the telephone, grasp the characteristics of the emergency telephone and the requirements of the emergency telephone.3.Guide students to understand the first aid instructions of the operators.4.Enable Ss to make simulated emergency calls with their partners in the language they have learned1. Instruct students to grasp the key information and important details of the dialogue.2. Instruct students to conduct a similar talk on the relevant topic.Step1:Look and discuss:Match the pictures below to the medical emergencies, and then discuss the questions in groups.
新人教版高中英語必修3Unit 4 Space Exploration-Discovering Useful Structures導學案
【點津】 1.不定式的復合結構作目的狀語 ,當不定式或不定式短語有自己的執(zhí)行者時，要用不定式的復合結構?即在不定式或不定式短語之前加 for ＋名詞或賓格代詞?作狀語。He opened the door for the children to come in. 他開門讓孩子們進來。目的狀語從句與不定式的轉換 英語中的目的狀語從句，還可以變?yōu)椴欢ㄊ交虿欢ㄊ蕉陶Z作狀語，從而使句子在結構上得以簡化?？煞譃閮煞N情況： 1?當目的狀語從句中的主語與主句中的主語相同時，可以直接簡化為不定式或不定式短語作狀語。We'll start early in order that/so that we may arrive in time. →We'll start early in order to/so as to arrive in time. 2?當目的狀語從句中的主語與主句中的主語不相同時，要用動詞不定式的復合結構作狀語。I came early in order that you might read my report before the meeting. →I came early in order for you to read my report before the meeting.
新人教版高中英語必修2Unit 1 Cultural Heritage-Listening＆Speaking＆Talking教案
Listening and Speaking introduces the topic of “Take part in a youth project”. The listening text is an interview about an international youth cultural heritage protection project. More than 20 high school students from seven countries participated in the project. The reporter interviewed two participants Stephanie and Liu Bin. By listening to the text, students can understand the significance of cultural heritage protection, and teenagers can use their knowledge, combine their own interests and advantages, etc. to participate in the action of cultural heritage protection. Listening and Talking introduces the theme of "Talk about history and culture". The listening text is a dialogue between two tourists and tour guides when they visit the Kremlin, red square and surrounding buildings. The dialogue focuses on the functional items of "starting a conversation", which is used to politely and appropriately attract the attention of the others, so as to smoothly start a conversation or start a new topic. The purpose of this section is to guide students to understand the history and current situation of Chinese and foreign cultural heritage in their own tourism experiences or from other people's tourism experiences, explore the historical and cultural values, and be able to express accurately and appropriately in oral communication.1. Guide students to understand the content of listening texts in terms of the whole and key details; 2. Cultivate students' ability to guess the meaning of words in listening; discuss with their peers how to participate in cultural heritage protection activities.3. Instruct students to use functional sentences of the dialogue such as “I beg your pardon, but…” “Forgive me for asking, but…" and so on to start the conversation more politely and appropriately.
新人教版高中英語必修2Unit 2 Wildlife Protection-Listening &Speaking＆Talking教案
Listening and Speaking introduces the topic of “how to save endangered wildlife and help wildlife in their neighborhood.” Due to the continuous deterioration of the living environment, a large number of wild animals are always facing the threat of endangered or extinction. Listening and speaking period enables students to understand the fact and reason why wild species are disappearing from the earth at an amazing speed, and realize that human beings ought to enhance the awareness of protecting wild species as soon as possible.Listening and Talking introduces the theme of " how to help wildlife in Ss’ neighborhood.". Now there are many volunteers who spontaneously protect wild animals, carry out various activities according to local conditions, and contribute their own strength to local animal protection with practical actions. Middle school students are also enthusiastic participants. They organize activities in their spare time, and take this opportunity to make friends, broaden their horizons, cultivate team spirit and communication skills. This section describes a bird watching activity organized by several middle school students of Bird watching Club. It aims to stimulate students' interest, improve their understanding of bird watching activities, and use the language structure of “being used for; in order to, so as to, to, so that, in order that ” to express the purpose for communication and discussion.1. Guide students to understand the content of listening texts in terms of using visuals to predict content.2. Cultivate students' ability to guess the meaning of words in listening; discuss with their peers how to save endangered wildlife and help wildlife in their neighborhood.3. Instruct students to use functional sentences of the dialogue such as “I am concerned about…” “what do you know about the endangered animals in…" and so on to talk about one of the endangered animals.
新人教版高中英語必修2Unit 5 Music-Listening＆Speaking＆Talking教案
choir memberspeople to run food stands people to sell festival ticketspeople to sell music CDspeople to set up equipmentmusical performersStep 2: Listen to the announcement again and answer the questions. ? 1. What kind of songs will Grace Davis sing at the festival?? 2. Who can try out as a performer?? 3. What can those who think they do not have musical talent do?? 4. How can students volunteer to take part?? Talking about preferences:? Would you prefer doing ..?? What would you prefer to do?? Would you rather do .... or ….?? What would you rather do?? I'd prefer .... to ..? I'd rather have ... than .. Step 3: Speaking ProjectWork in groups. Role-play the conversation or make a new one.? Debbie: Where have you been? You missed the announcement about the music festival.? John: I was at the doctor's office. Music festival?? Frank: Yes, it's going to be next month on the school sports field. John, you can play the piano. How about playing it at the festival?? John: Well, I'd rather play the violin. I can play Liang Zhu.? Frank: Wow! Sounds good. What about you, Debbie? ? Debbie: Actually, I don't have much musical ability. I'd prefer just to help out with the crowds.? Frank: You can sell tickets or work at a food stand.? John: So can I assume that the aim of the festival is to raise money?? Debbie: Yes. All of the money will go to charity.
人教A版高中數(shù)學必修二簡單隨機抽樣教學設計
知識探究（一）：普查與抽查像人口普查這樣，對每一個調(diào)查調(diào)查對象都進行調(diào)查的方法，稱為全面調(diào)查（又稱普查）。 在一個調(diào)查中，我們把調(diào)查對象的全體稱為總體，組成總體的每一個調(diào)查對象稱為個體。為了強調(diào)調(diào)查目的，也可以把調(diào)查對象的某些指標的全體作為總體，每一個調(diào)查對象的相應指標作為個體。問題二：除了普查，還有其他的調(diào)查方法嗎？由于人口普查需要花費巨大的財力、物力，因而不宜經(jīng)常進行。為了及時掌握全國人口變動狀況，我國每年還會進行一次人口變動情況的調(diào)查，根據(jù)抽取的居民情況來推斷總體的人口變動情況。像這樣，根據(jù)一定目的，從總體中抽取一部分個體進行調(diào)查，并以此為依據(jù)對總體的情況作出估計和判斷的方法，稱為抽樣調(diào)查（或稱抽查）。我們把從總體中抽取的那部分個體稱為樣本，樣本中包含的個體數(shù)稱為樣本量。
新人教版高中英語選修2Unit 4 Journey Across a Vast Land教學設計
當孩子們由父母陪同時，他們才被允許進入這個運動場。3．過去分詞(短語)作狀語時的幾種特殊情況(1)過去分詞(短語)在句中作時間、條件、原因、讓步狀語時，相當于對應的時間、條件、原因及讓步狀語從句。Seen from the top of the mountain (＝When it is seen from the top of the mountain), the whole town looks more beautiful.從山頂上看，整個城市看起來更美了。Given ten more minutes (＝If we are given ten more minutes), we will finish the work perfectly.如果多給十分鐘，我們會完美地完成這項工作。Greatly touched by his words (＝Because she was greatly touched by his words), she was full of tears.由于被他的話深深地感動，她滿眼淚花。Warned of the storm (＝Though they were warned of the storm), the farmers were still working on the farm.盡管被警告了風暴的到來，但農(nóng)民們?nèi)栽谵r(nóng)場干活。(2)過去分詞(短語)在句中作伴隨、方式等狀語時，可改為句子的并列謂語或改為并列分句。The teacher came into the room, followed by two students (＝and was followed by two students)．后面跟著兩個學生，老師走進了房間。He spent the whole afternoon, accompanied by his mom(＝and was accompanied by his mom)．他由母親陪著度過了一整個下午。
人教版高中數(shù)學選擇性必修二等差數(shù)列的前n項和公式（1）教學設計
高斯（Gauss，1777－1855），德國數(shù)學家，近代數(shù)學的奠基者之一. 他在天文學、大地測量學、磁學、光學等領域都做出過杰出貢獻. 問題1：為什么1＋100＝2＋99＝…＝50＋51呢？這是巧合嗎？試從數(shù)列角度給出解釋.高斯的算法：（1+100）+（2+99）+…+(50+51)= 101×50=5050高斯的算法實際上解決了求等差數(shù)列：1，2，3，…，n，"… " 前100項的和問題.等差數(shù)列中，下標和相等的兩項和相等.設 an＝n，則 a1＝1，a2＝2，a3＝3，…如果數(shù)列{an} 是等差數(shù)列，p，q，s，t∈N*，且 p＋q＝s＋t，則 ap＋aq＝as＋at 可得：a_1+a_100=a_2+a_99=?=a_50+a_51問題2： 你能用上述方法計算1＋2＋3＋… ＋101嗎？問題3： 你能計算1＋2＋3＋… ＋n嗎？需要對項數(shù)的奇偶進行分類討論.當n為偶數(shù)時， S_n=(1+n)+[(2+(n-1)]+?+[(n/2+(n/2-1)]=(1+n)+(1+n)…+(1+n)=n/2 (1+n) =(n(1+n))/2當n為奇數(shù)數(shù)時， n－1為偶數(shù)
人教版高中數(shù)學選擇性必修二等比數(shù)列的前n項和公式 (2) 教學設計
二、典例解析例10. 如圖，正方形ABCD 的邊長為5cm ，取正方形ABCD 各邊的中點E,F,G,H, 作第2個正方形 EFGH，然后再取正方形EFGH各邊的中點I,J,K,L，作第3個正方形IJKL ，依此方法一直繼續(xù)下去. (1) 求從正方形ABCD 開始，連續(xù)10個正方形的面積之和；(2) 如果這個作圖過程可以一直繼續(xù)下去，那么所有這些正方形的面積之和將趨近于多少？分析：可以利用數(shù)列表示各正方形的面積，根據(jù)條件可知，這是一個等比數(shù)列。解：設正方形的面積為a_1，后續(xù)各正方形的面積依次為a_2, a_(3, ) 〖…,a〗_n,…，則a_1=25,由于第k+1個正方形的頂點分別是第k個正方形各邊的中點，所以a_(k+1)=〖1/2 a〗_k,因此{a_n}，是以25為首項，1/2為公比的等比數(shù)列.設{a_n}的前項和為S_n（1）S_10=(25×[1-(1/2)^10 ] )/("1 " -1/2)=50×[1-(1/2)^10 ]=25575/512所以，前10個正方形的面積之和為25575/512cm^2.(2)當無限增大時，無限趨近于所有正方形的面積和
人教版高中數(shù)學選擇性必修二等比數(shù)列的概念 (1) 教學設計
新知探究我們知道，等差數(shù)列的特征是“從第2項起，每一項與它的前一項的差都等于同一個常數(shù)” 。類比等差數(shù)列的研究思路和方法，從運算的角度出發(fā)，你覺得還有怎樣的數(shù)列是值得研究的？1.兩河流域發(fā)掘的古巴比倫時期的泥版上記錄了下面的數(shù)列:9,9^2,9^3,…,9^10; ①100,100^2,100^3,…,100^10; ②5,5^2,5^3,…,5^10. ③2.《莊子·天下》中提到：“一尺之錘，日取其半，萬世不竭.”如果把“一尺之錘”的長度看成單位“1”，那么從第1天開始，每天得到的“錘”的長度依次是1/2,1/4,1/8,1/16,1/32,… ④3.在營養(yǎng)和生存空間沒有限制的情況下，某種細菌每20 min 就通過分裂繁殖一代，那么一個這種細菌從第1次分裂開始，各次分裂產(chǎn)生的后代個數(shù)依次是2,4,8,16,32,64,… ⑤4.某人存入銀行a元，存期為5年，年利率為 r ，那么按照復利，他5年內(nèi)每年末得到的本利和分別是a(1+r),a〖(1+r)〗^2,a〖(1+r)〗^3,a〖(1+r)〗^4,a〖(1+r)〗^5 ⑥
人教版高中數(shù)學選擇性必修二變化率問題教學設計
導語在必修第一冊中，我們研究了函數(shù)的單調(diào)性，并利用函數(shù)單調(diào)性等知識，定性的研究了一次函數(shù)、指數(shù)函數(shù)、對數(shù)函數(shù)增長速度的差異，知道“對數(shù)增長” 是越來越慢的，“指數(shù)爆炸” 比“直線上升” 快得多，進一步的能否精確定量的刻畫變化速度的快慢呢，下面我們就來研究這個問題。新知探究問題1 高臺跳水運動員的速度高臺跳水運動中，運動員在運動過程中的重心相對于水面的高度h(單位：m)與起跳后的時間t(單位：s)存在函數(shù)關系h(t)＝－4.9t2＋4.8t＋11.如何描述用運動員從起跳到入水的過程中運動的快慢程度呢？直覺告訴我們，運動員從起跳到入水的過程中，在上升階段運動的越來越慢，在下降階段運動的越來越快，我們可以把整個運動時間段分成許多小段，用運動員在每段時間內(nèi)的平均速度v ?近似的描述它的運動狀態(tài)。
人教版高中數(shù)學選擇性必修二導數(shù)的四則運算法則教學設計
求函數(shù)的導數(shù)的策略(1)先區(qū)分函數(shù)的運算特點，即函數(shù)的和、差、積、商，再根據(jù)導數(shù)的運算法則求導數(shù)；(2)對于三個以上函數(shù)的積、商的導數(shù)，依次轉化為“兩個”函數(shù)的積、商的導數(shù)計算．跟蹤訓練1 求下列函數(shù)的導數(shù)：(1)y＝x2＋log3x； (2)y＝x3·ex； (3)y＝cos xx.[解] (1)y′＝(x2＋log3x)′＝(x2)′＋(log3x)′＝2x＋1xln 3.(2)y′＝(x3·ex)′＝(x3)′·ex＋x3·(ex)′＝3x2·ex＋x3·ex＝ex(x3＋3x2)．(3)y′＝cos xx′＝?cos x?′·x－cos x·?x?′x2＝－x·sin x－cos xx2＝－xsin x＋cos xx2.跟蹤訓練2 求下列函數(shù)的導數(shù)（1）y＝tan x； （2）y＝2sin x2cos x2解析：（1）y＝tan x＝sin xcos x，故y′＝?sin x?′cos x－?cos x?′sin x?cos x?2＝cos2x＋sin2xcos2x＝1cos2x.（2）y＝2sin x2cos x2＝sin x，故y′＝cos x.例5 日常生活中的飲用水通常是經(jīng)過凈化的，隨著水的純凈度的提高，所需進化費用不斷增加，已知將1t水進化到純凈度為x%所需費用（單位：元），為c(x)=5284/(100-x) (80<x<100)求進化到下列純凈度時，所需進化費用的瞬時變化率：（1） 90% ；（2） 98%解：凈化費用的瞬時變化率就是凈化費用函數(shù)的導數(shù)；c^' (x)=〖(5284/(100-x))〗^'=(5284^’×(100-x)-"5284 " 〖(100-x)〗^’)/〖(100-x)〗^2 =(0×(100-x)-"5284 " ×(-1))/〖(100-x)〗^2 ="5284 " /〖(100-x)〗^2
人教版高中數(shù)學選擇性必修二導數(shù)的概念及其幾何意義教學設計
新知探究前面我們研究了兩類變化率問題：一類是物理學中的問題，涉及平均速度和瞬時速度；另一類是幾何學中的問題，涉及割線斜率和切線斜率。這兩類問題來自不同的學科領域，但在解決問題時，都采用了由“平均變化率”逼近“瞬時變化率”的思想方法；問題的答案也是一樣的表示形式。下面我們用上述思想方法研究更一般的問題。探究1： 對于函數(shù)y=f(x) ，設自變量x從x_0變化到x_0+ ?x ，相應地，函數(shù)值y就從f(x_0)變化到f(〖x+x〗_0) 。這時， x的變化量為?x，y的變化量為?y=f(x_0+?x)-f(x_0)我們把比值?y/?x，即?y/?x=(f(x_0+?x)-f(x_0)" " )/?x叫做函數(shù)從x_0到x_0+?x的平均變化率。1．導數(shù)的概念如果當Δx→0時，平均變化率ΔyΔx無限趨近于一個確定的值，即ΔyΔx有極限，則稱y＝f (x)在x＝x0處____，并把這個________叫做y＝f (x)在x＝x0處的導數(shù)(也稱為__________)，記作f ′(x0)或________，即
