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新人教版高中英語(yǔ)選修2Unit 3 Reading for writing教學(xué)設(shè)計(jì)
The theme of this part is to write an article about healthy diet. Through reading and writing activities, students can accumulate knowledge about healthy diet, deepen their understanding of the theme of healthy diet, and reflect on their own eating habits. This text describes the basic principles of healthy diet. The author uses data analysis, definition, comparison, examples and other methods. It also provides a demonstration of the use of conjunctions, which provides important information reference for students to complete the next collaborative task, writing skills, vivid language materials and expressions.1. Teach Ss to learn and skillfully use the new words learned from the text.2. Develop students’ ability to understand, extract and summarize information.3. Guide students to understand the theme of healthy diet and reflect on their own eating habits.4. To guide students to analyze and understand the reading discourse from the aspects of theme content, writing structure, language expression, etc., 5. Enable Ss to write in combination with relevant topics and opinions, and to talk about their eating habits.1. Guide students to analyze and understand the reading discourse from the aspects of theme content, writing structure, language expression, etc.2. Enable them to write in combination with relevant topics and opinions, and to talk about their eating habits.3. Guide the students to use the cohesive words correctly, strengthen the textual cohesion, and make the expression fluent and the thinking clear.Step1: Warming upbrainstorm some healthy eating habits.1.Eat slowly.2.Don’t eat too much fat or sugar.3.Eat healthy food.4.Have a balanced diet.Step2: Read the passage and then sum up the main idea of each paragraph.
新人教版高中英語(yǔ)選修2Unit 2 Bridging Cultures-Discovering useful structures教學(xué)設(shè)計(jì)
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.
人教A版高中數(shù)學(xué)必修二簡(jiǎn)單隨機(jī)抽樣教學(xué)設(shè)計(jì)
知識(shí)探究（一）：普查與抽查像人口普查這樣，對(duì)每一個(gè)調(diào)查調(diào)查對(duì)象都進(jìn)行調(diào)查的方法，稱為全面調(diào)查（又稱普查）。 在一個(gè)調(diào)查中，我們把調(diào)查對(duì)象的全體稱為總體，組成總體的每一個(gè)調(diào)查對(duì)象稱為個(gè)體。為了強(qiáng)調(diào)調(diào)查目的，也可以把調(diào)查對(duì)象的某些指標(biāo)的全體作為總體，每一個(gè)調(diào)查對(duì)象的相應(yīng)指標(biāo)作為個(gè)體。問(wèn)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(fèi)巨大的財(cái)力、物力，因而不宜經(jīng)常進(jìn)行。為了及時(shí)掌握全國(guó)人口變動(dòng)狀況，我國(guó)每年還會(huì)進(jìn)行一次人口變動(dòng)情況的調(diào)查，根據(jù)抽取的居民情況來(lái)推斷總體的人口變動(dòng)情況。像這樣，根據(jù)一定目的，從總體中抽取一部分個(gè)體進(jìn)行調(diào)查，并以此為依據(jù)對(duì)總體的情況作出估計(jì)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(gè)體稱為樣本，樣本中包含的個(gè)體數(shù)稱為樣本量。
人教版高中數(shù)學(xué)選擇性必修二等差數(shù)列的前n項(xiàng)和公式（1）教學(xué)設(shè)計(jì)
高斯（Gauss，1777－1855），德國(guó)數(shù)學(xué)家，近代數(shù)學(xué)的奠基者之一. 他在天文學(xué)、大地測(cè)量學(xué)、磁學(xué)、光學(xué)等領(lǐng)域都做出過(guò)杰出貢獻(xiàn). 問(wèn)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(shí)際上解決了求等差數(shù)列：1，2，3，…，n，"… " 前100項(xiàng)的和問(wèn)題.等差數(shù)列中，下標(biāo)和相等的兩項(xiàng)和相等.設(shè) 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(wèn)題2： 你能用上述方法計(jì)算1＋2＋3＋… ＋101嗎？問(wèn)題3： 你能計(jì)算1＋2＋3＋… ＋n嗎？需要對(duì)項(xiàng)數(shù)的奇偶進(jìn)行分類討論.當(dāng)n為偶數(shù)時(shí)， 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(dāng)n為奇數(shù)數(shù)時(shí)， n－1為偶數(shù)
人教版高中數(shù)學(xué)選擇性必修二等比數(shù)列的概念 (1) 教學(xué)設(shè)計(jì)
新知探究我們知道，等差數(shù)列的特征是“從第2項(xiàng)起，每一項(xiàng)與它的前一項(xiàng)的差都等于同一個(gè)常數(shù)” 。類比等差數(shù)列的研究思路和方法，從運(yùn)算的角度出發(fā)，你覺(jué)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(shí)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(wàn)世不竭.”如果把“一尺之錘”的長(zhǎng)度看成單位“1”，那么從第1天開(kāi)始，每天得到的“錘”的長(zhǎng)度依次是1/2,1/4,1/8,1/16,1/32,… ④3.在營(yíng)養(yǎng)和生存空間沒(méi)有限制的情況下，某種細(xì)菌每20 min 就通過(guò)分裂繁殖一代，那么一個(gè)這種細(xì)菌從第1次分裂開(kāi)始，各次分裂產(chǎn)生的后代個(gè)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(fù)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(xué)選擇性必修二變化率問(wèn)題教學(xué)設(shè)計(jì)
導(dǎo)語(yǔ)在必修第一冊(cè)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(shí)，定性的研究了一次函數(shù)、指數(shù)函數(shù)、對(duì)數(shù)函數(shù)增長(zhǎng)速度的差異，知道“對(duì)數(shù)增長(zhǎng)” 是越來(lái)越慢的，“指數(shù)爆炸” 比“直線上升” 快得多，進(jìn)一步的能否精確定量的刻畫(huà)變化速度的快慢呢，下面我們就來(lái)研究這個(gè)問(wèn)題。新知探究問(wèn)題1 高臺(tái)跳水運(yùn)動(dòng)員的速度高臺(tái)跳水運(yùn)動(dòng)中，運(yùn)動(dòng)員在運(yùn)動(dòng)過(guò)程中的重心相對(duì)于水面的高度h(單位：m)與起跳后的時(shí)間t(單位：s)存在函數(shù)關(guān)系h(t)＝－4.9t2＋4.8t＋11.如何描述用運(yùn)動(dòng)員從起跳到入水的過(guò)程中運(yùn)動(dòng)的快慢程度呢？直覺(jué)告訴我們，運(yùn)動(dòng)員從起跳到入水的過(guò)程中，在上升階段運(yùn)動(dòng)的越來(lái)越慢，在下降階段運(yùn)動(dòng)的越來(lái)越快，我們可以把整個(gè)運(yùn)動(dòng)時(shí)間段分成許多小段，用運(yùn)動(dòng)員在每段時(shí)間內(nèi)的平均速度v ?近似的描述它的運(yùn)動(dòng)狀態(tài)。
人教版高中數(shù)學(xué)選擇性必修二導(dǎo)數(shù)的四則運(yùn)算法則教學(xué)設(shè)計(jì)
求函數(shù)的導(dǎo)數(shù)的策略(1)先區(qū)分函數(shù)的運(yùn)算特點(diǎn)，即函數(shù)的和、差、積、商，再根據(jù)導(dǎo)數(shù)的運(yùn)算法則求導(dǎo)數(shù)；(2)對(duì)于三個(gè)以上函數(shù)的積、商的導(dǎo)數(shù)，依次轉(zhuǎn)化為“兩個(gè)”函數(shù)的積、商的導(dǎo)數(shù)計(jì)算．跟蹤訓(xùn)練1 求下列函數(shù)的導(dǎo)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(xùn)練2 求下列函數(shù)的導(dǎo)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(guò)凈化的，隨著水的純凈度的提高，所需進(jìn)化費(fèi)用不斷增加，已知將1t水進(jìn)化到純凈度為x%所需費(fèi)用（單位：元），為c(x)=5284/(100-x) (80<x<100)求進(jìn)化到下列純凈度時(shí)，所需進(jìn)化費(fèi)用的瞬時(shí)變化率：（1） 90% ；（2） 98%解：凈化費(fèi)用的瞬時(shí)變化率就是凈化費(fèi)用函數(shù)的導(dǎo)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(xué)選擇性必修二等比數(shù)列的概念 (2) 教學(xué)設(shè)計(jì)
二、典例解析例4. 用 10 000元購(gòu)買某個(gè)理財(cái)產(chǎn)品一年.（1）若以月利率0.400%的復(fù)利計(jì)息，12個(gè)月能獲得多少利息（精確到1元）？（2）若以季度復(fù)利計(jì)息，存4個(gè)季度，則當(dāng)每季度利率為多少時(shí)，按季結(jié)算的利息不少于按月結(jié)算的利息（精確到10^(-5)）？分析：復(fù)利是指把前一期的利息與本金之和算作本金，再計(jì)算下一期的利息.所以若原始本金為a元，每期的利率為r ，則從第一期開(kāi)始，各期的本利和a , a(1+r)，a(1+r)^2…構(gòu)成等比數(shù)列.解：（1）設(shè)這筆錢存 n 個(gè)月以后的本利和組成一個(gè)數(shù)列{a_n }，則{a_n }是等比數(shù)列，首項(xiàng)a_1=10^4 (1+0.400%)，公比 q=1+0.400%，所以a_12=a_1 q^11 〖=10〗^4 (1+0.400%)^12≈10 490.7.所以，12個(gè)月后的利息為10 490.7-10^4≈491（元）.解：（2）設(shè)季度利率為 r ，這筆錢存 n 個(gè)季度以后的本利和組成一個(gè)數(shù)列{b_n }，則{b_n }也是一個(gè)等比數(shù)列，首項(xiàng) b_1=10^4 (1+r)，公比為1+r，于是 b_4=10^4 (1+r)^4.
人教版高中數(shù)學(xué)選擇性必修二等差數(shù)列的前n項(xiàng)和公式（2）教學(xué)設(shè)計(jì)
課前小測(cè)1．思考辨析(1)若Sn為等差數(shù)列{an}的前n項(xiàng)和，則數(shù)列Snn也是等差數(shù)列．( )(2)若a1>0，d<0，則等差數(shù)列中所有正項(xiàng)之和最大．( )(3)在等差數(shù)列中，Sn是其前n項(xiàng)和，則有S2n－1＝(2n－1)an.( )[答案] (1)√ (2)√ (3)√2．在項(xiàng)數(shù)為2n＋1的等差數(shù)列中，所有奇數(shù)項(xiàng)的和為165，所有偶數(shù)項(xiàng)的和為150，則n等于( )A．9 B．10 C．11 D．12B [∵S奇S偶＝n＋1n，∴165150＝n＋1n.∴n＝10.故選B項(xiàng)．]3．等差數(shù)列{an}中，S2＝4，S4＝9，則S6＝________.15 [由S2，S4－S2，S6－S4成等差數(shù)列得2(S4－S2)＝S2＋(S6－S4)解得S6＝15.]4．已知數(shù)列{an}的通項(xiàng)公式是an＝2n－48，則Sn取得最小值時(shí)，n為_(kāi)_______.23或24 [由an≤0即2n－48≤0得n≤24.∴所有負(fù)項(xiàng)的和最小，即n＝23或24.]二、典例解析例8.某校新建一個(gè)報(bào)告廳，要求容納800個(gè)座位，報(bào)告廳共有20排座位，從第2排起后一排都比前一排多兩個(gè)座位. 問(wèn)第1排應(yīng)安排多少個(gè)座位？分析：將第1排到第20排的座位數(shù)依次排成一列，構(gòu)成數(shù)列{an} ，設(shè)數(shù)列{an} 的前n項(xiàng)和為S_n。
人教版高中數(shù)學(xué)選擇性必修二函數(shù)的單調(diào)性(1) 教學(xué)設(shè)計(jì)
1．判斷正誤(正確的打“√”，錯(cuò)誤的打“×”)(1)函數(shù)f (x)在區(qū)間(a，b)上都有f ′(x)＜0，則函數(shù)f (x)在這個(gè)區(qū)間上單調(diào)遞減． ( )(2)函數(shù)在某一點(diǎn)的導(dǎo)數(shù)越大，函數(shù)在該點(diǎn)處的切線越“陡峭”． ( )(3)函數(shù)在某個(gè)區(qū)間上變化越快，函數(shù)在這個(gè)區(qū)間上導(dǎo)數(shù)的絕對(duì)值越大．( )(4)判斷函數(shù)單調(diào)性時(shí)，在區(qū)間內(nèi)的個(gè)別點(diǎn)f ′(x)＝0，不影響函數(shù)在此區(qū)間的單調(diào)性．( )[解析] (1)√ 函數(shù)f (x)在區(qū)間(a，b)上都有f ′(x)＜0，所以函數(shù)f (x)在這個(gè)區(qū)間上單調(diào)遞減，故正確．(2)× 切線的“陡峭”程度與|f ′(x)|的大小有關(guān)，故錯(cuò)誤．(3)√ 函數(shù)在某個(gè)區(qū)間上變化的快慢，和函數(shù)導(dǎo)數(shù)的絕對(duì)值大小一致．(4)√ 若f ′(x)≥0(≤0)，則函數(shù)f (x)在區(qū)間內(nèi)單調(diào)遞增(減)，故f ′(x)＝0不影響函數(shù)單調(diào)性．[答案] (1)√ (2)× (3)√ (4)√例1. 利用導(dǎo)數(shù)判斷下列函數(shù)的單調(diào)性:（1）f(x)=x^3+3x; （2） f(x)=sinx-x,x∈(0,π); (3)f(x)=(x-1)/x解: (1) 因?yàn)閒(x)=x^3+3x, 所以f^' (x)=〖3x〗^2+3=3(x^2+1)>0所以f(x)=x^3+3x ，函數(shù)在R上單調(diào)遞增，如圖（1）所示
人教版高中數(shù)學(xué)選擇性必修二導(dǎo)數(shù)的概念及其幾何意義教學(xué)設(shè)計(jì)
新知探究前面我們研究了兩類變化率問(wèn)題：一類是物理學(xué)中的問(wèn)題，涉及平均速度和瞬時(shí)速度；另一類是幾何學(xué)中的問(wèn)題，涉及割線斜率和切線斜率。這兩類問(wèn)題來(lái)自不同的學(xué)科領(lǐng)域，但在解決問(wèn)題時(shí)，都采用了由“平均變化率”逼近“瞬時(shí)變化率”的思想方法；問(wèn)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(wèn)題。探究1： 對(duì)于函數(shù)y=f(x) ，設(shè)自變量x從x_0變化到x_0+ ?x ，相應(yīng)地，函數(shù)值y就從f(x_0)變化到f(〖x+x〗_0) 。這時(shí)， 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(dǎo)數(shù)的概念如果當(dāng)Δx→0時(shí)，平均變化率ΔyΔx無(wú)限趨近于一個(gè)確定的值，即ΔyΔx有極限，則稱y＝f (x)在x＝x0處____，并把這個(gè)________叫做y＝f (x)在x＝x0處的導(dǎo)數(shù)(也稱為_(kāi)_________)，記作f ′(x0)或________，即
人教版高中數(shù)學(xué)選擇性必修二等差數(shù)列的概念（1）教學(xué)設(shè)計(jì)
我們知道數(shù)列是一種特殊的函數(shù)，在函數(shù)的研究中，我們?cè)诶斫饬撕瘮?shù)的一般概念，了解了函數(shù)變化規(guī)律的研究?jī)?nèi)容（如單調(diào)性，奇偶性等）后，通過(guò)研究基本初等函數(shù)不僅加深了對(duì)函數(shù)的理解，而且掌握了冪函數(shù)，指數(shù)函數(shù)，對(duì)數(shù)函數(shù)，三角函數(shù)等非常有用的函數(shù)模型。類似地，在了解了數(shù)列的一般概念后，我們要研究一些具有特殊變化規(guī)律的數(shù)列，建立它們的通項(xiàng)公式和前n項(xiàng)和公式，并應(yīng)用它們解決實(shí)際問(wèn)題和數(shù)學(xué)問(wèn)題，從中感受數(shù)學(xué)模型的現(xiàn)實(shí)意義與應(yīng)用，下面，我們從一類取值規(guī)律比較簡(jiǎn)單的數(shù)列入手。新知探究1.北京天壇圜丘壇，的地面有十板布置，最中間是圓形的天心石，圍繞天心石的是9圈扇環(huán)形的石板，從內(nèi)到外各圈的示板數(shù)依次為9,18,27,36,45,54,63,72,81 ①2.S，M，L，XL，XXL，XXXL型號(hào)的女裝上對(duì)應(yīng)的尺碼分別是38,40,42,44,46,48 ②3.測(cè)量某地垂直地面方向上海拔500米以下的大氣溫度，得到從距離地面20米起每升高100米處的大氣溫度（單位℃）依次為25,24,23,22,21 ③
人教版高中數(shù)學(xué)選擇性必修二等差數(shù)列的概念（2）教學(xué)設(shè)計(jì)
二、典例解析例3.某公司購(gòu)置了一臺(tái)價(jià)值為220萬(wàn)元的設(shè)備，隨著設(shè)備在使用過(guò)程中老化，其價(jià)值會(huì)逐年減少.經(jīng)驗(yàn)表明，每經(jīng)過(guò)一年其價(jià)值會(huì)減少d(d為正常數(shù)）萬(wàn)元.已知這臺(tái)設(shè)備的使用年限為10年，超過(guò)10年 ，它的價(jià)值將低于購(gòu)進(jìn)價(jià)值的5%，設(shè)備將報(bào)廢.請(qǐng)確定d的范圍.分析：該設(shè)備使用n年后的價(jià)值構(gòu)成數(shù)列{an}，由題意可知，an＝an－1－d (n≥2). 即：an－an－1＝－d.所以{an}為公差為－d的等差數(shù)列.10年之內(nèi)（含10年），該設(shè)備的價(jià)值不小于（220×5%=）11萬(wàn)元；10年后，該設(shè)備的價(jià)值需小于11萬(wàn)元．利用{an}的通項(xiàng)公式列不等式求解．解：設(shè)使用n年后，這臺(tái)設(shè)備的價(jià)值為an萬(wàn)元，則可得數(shù)列{an}．由已知條件，得an＝an－1－d（n≥2）．所以數(shù)列{an}是一個(gè)公差為－d的等差數(shù)列.因?yàn)閍1＝220－d，所以an＝220－d＋(n－1)(－d)＝220－nd. 由題意，得a10≥11，a11＜11. 即：{█("220－10d≥11" @"220－11d＜11" )┤解得19<d≤20.9所以，d的求值范圍為19<d≤20.9
人教版高中數(shù)學(xué)選擇性必修二等比數(shù)列的前n項(xiàng)和公式 (1) 教學(xué)設(shè)計(jì)
新知探究國(guó)際象棋起源于古代印度.相傳國(guó)王要獎(jiǎng)賞國(guó)際象棋的發(fā)明者，問(wèn)他想要什么.發(fā)明者說(shuō)：“請(qǐng)?jiān)谄灞P(pán)的第1個(gè)格子里放上1顆麥粒，第2個(gè)格子里放上2顆麥粒，第3個(gè)格子里放上4顆麥粒，依次類推，每個(gè)格子里放的麥粒都是前一個(gè)格子里放的麥粒數(shù)的2倍，直到第64個(gè)格子.請(qǐng)給我足夠的麥粒以實(shí)現(xiàn)上述要求.”國(guó)王覺(jué)得這個(gè)要求不高，就欣然同意了.假定千粒麥粒的質(zhì)量為40克，據(jù)查，2016--2017年度世界年度小麥產(chǎn)量約為7.5億噸，根據(jù)以上數(shù)據(jù)，判斷國(guó)王是否能實(shí)現(xiàn)他的諾言.問(wèn)題1：每個(gè)格子里放的麥粒數(shù)可以構(gòu)成一個(gè)數(shù)列,請(qǐng)判斷分析這個(gè)數(shù)列是否是等比數(shù)列?并寫(xiě)出這個(gè)等比數(shù)列的通項(xiàng)公式.是等比數(shù)列,首項(xiàng)是1，公比是2，共64項(xiàng). 通項(xiàng)公式為〖a_n=2〗^(n-1)問(wèn)題2：請(qǐng)將發(fā)明者的要求表述成數(shù)學(xué)問(wèn)題.
人教版高中數(shù)學(xué)選擇性必修二數(shù)列的概念（1）教學(xué)設(shè)計(jì)
情景導(dǎo)學(xué)古語(yǔ)云:“勤學(xué)如春起之苗,不見(jiàn)其增,日有所長(zhǎng)”如果對(duì)“春起之苗”每日用精密儀器度量,則每日的高度值按日期排在一起,可組成一個(gè)數(shù)列. 那么什么叫數(shù)列呢?二、問(wèn)題探究1. 王芳從一歲到17歲，每年生日那天測(cè)量身高，將這些身高數(shù)據(jù)（單位：厘米）依次排成一列數(shù)：75,87,96,103,110,116,120,128,138，145,153,158,160,162,163,165,168 ①記王芳第i歲的身高為 h_i ，那么h_1=75 , h_2=87, 〖"…" ，h〗_17=168.我們發(fā)現(xiàn)h_i中的i反映了身高按歲數(shù)從1到17的順序排列時(shí)的確定位置，即h_1=75 是排在第1位的數(shù)，h_2=87是排在第2位的數(shù)〖"…" ，h〗_17 =168是排在第17位的數(shù)，它們之間不能交換位置，所以①具有確定順序的一列數(shù)。2. 在兩河流域發(fā)掘的一塊泥板（編號(hào)K90，約生產(chǎn)于公元前7世紀(jì)）上，有一列依次表示一個(gè)月中從第1天到第15天，每天月亮可見(jiàn)部分的數(shù)：5,10,20,40,80,96,112,128,144,160,176,192,208,224,240. ②
人教版高中數(shù)學(xué)選擇性必修二等比數(shù)列的前n項(xiàng)和公式 (2) 教學(xué)設(shè)計(jì)
二、典例解析例10. 如圖，正方形ABCD 的邊長(zhǎng)為5cm ，取正方形ABCD 各邊的中點(diǎn)E,F,G,H, 作第2個(gè)正方形 EFGH，然后再取正方形EFGH各邊的中點(diǎn)I,J,K,L，作第3個(gè)正方形IJKL ，依此方法一直繼續(xù)下去. (1) 求從正方形ABCD 開(kāi)始，連續(xù)10個(gè)正方形的面積之和；(2) 如果這個(gè)作圖過(guò)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(gè)等比數(shù)列。解：設(shè)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(gè)正方形的頂點(diǎn)分別是第k個(gè)正方形各邊的中點(diǎn)，所以a_(k+1)=〖1/2 a〗_k,因此{(lán)a_n}，是以25為首項(xiàng)，1/2為公比的等比數(shù)列.設(shè){a_n}的前項(xiàng)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(gè)正方形的面積之和為25575/512cm^2.(2)當(dāng)無(wú)限增大時(shí)，無(wú)限趨近于所有正方形的面積和
新人教版高中英語(yǔ)選修2Unit 5 Reading for writing教學(xué)設(shè)計(jì)
你校英語(yǔ)報(bào)計(jì)劃出版一期急救常識(shí)?？?現(xiàn)面向全校學(xué)生公開(kāi)征集稿件,你有意參加。請(qǐng)你根據(jù)下面提示內(nèi)容,用英語(yǔ)寫(xiě)一篇短文,介紹在車禍現(xiàn)場(chǎng)對(duì)傷者進(jìn)行急救的方法和步驟。1.確?，F(xiàn)場(chǎng)的安全;2.詢問(wèn)傷者,確保其呼吸正常;3.檢查傷口,如流血?jiǎng)t應(yīng)采取止血措施;4.如需急救,確保其處于康復(fù)位置。注意:1.詞數(shù)80左右;2.可以適當(dāng)增加細(xì)節(jié),以使行文連貫。參考詞匯:康復(fù)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(yǔ)選修2Unit 4 Using langauge-Listening教學(xué)設(shè)計(jì)
The theme of the listening section is " talking about scenery and culture along a journey."The part is designed to further lead the students to understand Canadian natural geography and social environment, and integrated into the cultural contrast by mentioning the long train journey from Beijing to Moscow routes. On this basis, the part activates students related travel experience, lets the student serial dialogue, guides the student to explore further the pleasure and meaning of the long journey, and Chinese and foreign cultural comparison.The part also provides a framework for the continuation of the dialogue, which is designed to provide a framework for students to successfully complete their oral expressions, and to incorporate an important trading strategy to end the dialogue naturally.1. Help students to understand and master some common English idioms in the context, and experience the expression effect of English idioms.2. Guide the students to understand the identity of different people in the listening context, and finish the dialogue according to their own experience.3. Instruct the students to use appropriate language to express surprise and curiosity about space and place in the dialogue, and master the oral strategy of ending the dialogue naturally.1. 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.
新人教版高中英語(yǔ)選修2Unit 5 Learning about Language教學(xué)設(shè)計(jì)
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(yǔ)選修2Unit 5 Using langauge-Listening教學(xué)設(shè)計(jì)
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.
