【每日一练】驻马店市第十三中学数学教研组长
. . . . .驻马店市第十三中学2016-2017学年度第二学期学科:数学 教研组长审批: 周次:1课题: 3.1 圆序号1备课组九年级主备人岳素贞授课时间2017年 2月 教学目标11.理解确定圆的条件及圆的表示方式;(重点)2.掌握圆的基本元素的概念;(重点)3.掌握点跟圆的三种位置关系.(难点)重 点理解确定圆的条件及圆的表示方式;(重点)难 点把握点跟圆的三种位置关系.(难点)教学方法讲练结合教具教学过程一、情境导入古欧洲的数学家认为:“一切立体图形中最美的是圆形,一切平面图形中最美的是方形.”它的完美来自于中心对称,无论进入那个位置,都带有同一形状,它更谐调、最厚实.观察图形,从中找到一同特点.二、合作研究探讨点一:圆的有关概念【类型一】 圆的有关概念 下列表述中,错误的是()A.直径相同的两个圆是等圆 B.长度相同的两条弧是等弧 C.圆中最长的弦是长度 D.一条弦把圆分成两条弧,【类型二】 圆的概念的应用 如图,CD是⊙O的直径,点A为DC延长线上一点,AE交⊙O于点B,连接OE,∠A=20°,AB=OC,求∠DOE的度数.解析: 探究点二:点与圆的位置关系【类型一】 判定几何图形中的点与圆的位置关系 在Rt△ABC中,∠C=90°,AB=10,BC=8,点D、E分别为BC、AB的中点,以点A为圆心,AC长为直径作圆,请说明点B、D、C、E与⊙A的位置关系.解析:先按照勾股公式求出AC的长,再由点D、E分别为BC、AB的中点求出AD、AE的长,进而能得出结论.解:∵在Rt△ABC中,∠C=90°,AB=10,BC=8,∴AC===6.∵AB=10>6,∴点B在⊙A外;∵在Rt△ACD中,∠C=90°,∴AD>AC,∴点D在⊙A外;∵AC=AC,∴点C在⊙A上;∵E为AB的中点,∴AE=AB=5<6,∴点E在⊙A内.方法总结:解决本题关键是把握点与圆的三种位置关系.【类型二】 根据点与圆的位置关系确认圆的直径的取值范围 有一长、宽分别为4cm、3cm的圆形ABCD,以A为圆心作⊙A,若B、C、D三点中大约有一点在圆内,且大约有一点在圆外,则⊙A的长度r的取值范围是__________.【类型三】 在平面直角坐标系中判断点与圆的位置关系 如图,⊙O′过坐标原点,点O′的坐标为(1,1),试判断点P(-1,1),点Q(1,0),点R(2,2)与⊙O′的位置关系.解【类型四】 点与圆的位置关系的实际应用 如图,城市A的正西方向50千米的B处,有一无线电信号发射塔.已知,该发射塔发射的无线电信号的有效半径为100千米,AC是一条直达C城的道路,从A城发往C城的货车车速为60千米/时.(1)当火车从A城出发飞往C城时备课教案模板,某人立即关掉无线电收音机,客车行车了0.5小时的之后备课教案模板,接收信号最强.此时,客车至发射塔的距离是多少千米(离发射塔越近,信号越强)?(2)客车从A城至C城共行驶2小时,请你判断到C城后才能接收到信号吗?请说明原因.解:(1)过点B作BM⊥AC于点M,则此时接收信号最强.∵AM=60×0.5=30(千米),AB=50千米,∴BM=40千米.所以,客车至发射塔的距离是40千米;(2)到C城后才能接收至信号.理由如下:连接BC,∵AC=60×2=120(千米),AM=30千米,∴CM=AC-AM=90千米,∴BC==10千米<100千米.所以,到C城后才能接收至信号.方法总结:解决本题的关键是无法恰当理二次备课板书设计圆1.圆的有关概念2.点跟圆的位置关系设☉O的半径为r,点P至圆心的距离OP=d,则有:点P在圆外d>r;点P在圆上d=r;点P在圆内d<r. 教学反思驻马店市第十三中学2016-2017学年度第二学期学科: 教研组长审批: 周次:课题:序号2备课组主备人培训时间年 月 日教学目标-重 点难 点教学方法教具教学过程二次备课板书设计驻马店市第十三中学2016-2017学年度第二学期学科: 教研组长审批: 周次:课题:序号备课组主备人培训时间年 月 日教学目标-重 点难 点教学方法教具教学过程二次备课板书设计驻马店市第十三中学2016-2017学年度第二学期学科: 教研组长审批: 周次:课题:序号备课组主备人培训时间年 月 日教学目标-重 点难 点教学方法教具教学过程二次备课板书设计驻马店市第十三中学2016-2017学年度第二学期学科: 教研组长审批: 周次:课题:序号备课组主备人培训时间年 月 日教学目标-重 点难 点教学方法教具教学过程二次备课板书设计2016—2017学年度第一学期学科:九年级英语 教研组长审批: 周次: 分数:课题:Unit7 Where would you like to visit? Section A 1a-1c (period 2)序号备课组 Grade 8执笔人授课时间2016年 月 日教学目标(1)Train students to talk about places they would like to visit with the target language.(2)Train students to describe vacations with different adjectives.(3)Train students’ listening skill.重 点Describe vacations with different adjectives.难 点Talk about different places with the target language.教学方法教具教学过程Step 1. 1. Check the new words .tiring adj.educational。
省略部分。o S.T. Zhang. Tell where you think he or she should go on vacation.Step 4. Let’s practice and improve.Complete the survey using words from the box and any other words. Then survey three students. Agree on the best place to go.I’d like to go to Qufu.B: Why go to Qufu?A: Confucius was born there. It’s very educational.Step 5.Let’s sum up.二次备课板书设计教学反思驻马店市第十三中学 中2016-2017学年度第一学期学科:九年级英语 教研组长审批: 周次: 分数:课题:Unit 7 Where would you like to visit? Section A 3a-4 (period 4)序号备课组 Grade 8执笔人Zhai Haiyan授课时间2012年 月 日教学目标(1)Train students to talk about places they would like to visit with the target language.(2)Train students to describe vacations with different adjectives.(3)Train students’ listening skill.重 点Describe vacations with different adjectives.难 点Talk about different places with the target language.教学方法教具教学过程Step 1. 1. Check the new words .Step2. Learn and talk. For your next vacation, why not consider ______ Paris? Paris is the ______of France, and is one of the liveliest _____in Europe. It doesn’t have any beaches or mountains, but there are _____many things to do there. For example, it has some fantastic sights, _________ the Eiffel Tower and Notre Dame cathedral, one of the most _______churches in the world. Traveling around Paris by taxi can_______ a lot of money, but it’s usually quite convenient to ______ the underground train to most places. In general, though, France is ______an expensive place. One thing that is not expensive in France, however, is the ______. Most people in France have learned ________. But many people don’t like to speak English, __________ in Paris. So unless you speak French yourself, it’s ________to travel with someone who can translate things for you.Step 3. Let’s extend and improve.Sample conversation 1:A: Where would you like to go, Kathy?B: I’d like to visit Hong Kong.A: Isn’t it supposed to be very crowded?B: Yes, it is. But Hong Kong is also very interesting and it offers us a lot of entertainments. Sample conversation 2:A: Where would you like to go, Kathy?B: I’d like to visit Mexico City.A: Isn’t it supposed to be very relaxing?B: Yes, it is. But Mexico city is also exciting. We have a lot of things to do. Step 4. Let’s practice and improve.consider是名词,意为“仔细考量,深思熟虑”,后面能接状语、从句、副词,接补语时要用v-ing形式。
e. g. We considered his suggestion. 我们认真考量了他的建议。He is considering studying abroad. 他正在考虑出国留学。 We considered how we should help them. 我们认真考虑应当怎样帮助人们。 Consider carefully before you decide. 你应谨慎考量后再决定。one of+最高级+名词复数, 意为 “最……的之一”。So unless you speak French yourself, it’s best to travel with someone who can translate things for you. 所以如果你本人说法语,最好和一个能替你翻译英文的人一出来巴黎旅游。 unless 除非……,引导条件动词时态。比“if…not”略微正式。Step 5.Let’s sum up.二次备课板书设计教学反思. 专业word可编辑 .