高中数学人教版选修1-1课件第2章-圆锥曲线与方程212.ppt

1、成才之路成才之路数学数学路漫漫其修远兮吾将上下而求索路漫漫其修远兮吾将上下而求索人教人教A版版选修选修1-11-2圆锥曲线与方程圆锥曲线与方程第二章第二章2.1椭圆椭圆第二章第二章2.1.2椭圆的简单几何性质椭圆的简单几何性质课堂典例讲练课堂典例讲练2课课 时时 作作 业业3课前自主预习课前自主预习1课前自主预习课前自主预习“天宫一号”的运行轨迹是椭圆形的，椭圆在我们的生活中经常出现，你知道椭圆有什么样的性质吗？椭圆的简单几何性质x轴、y轴原点焦点的位置焦点在x轴上焦点在y轴上范围x_，y_x_，y_顶点_轴长长轴|A1A2|_，短轴|B1B2|_焦点_焦距|F1F2|_离心率e_(0e1)a

2、，ab，bb，ba，a(a,0)(0，b)(0，a)(b,0)2a2b(c,0)(0，c)2c答案C解析由方程可知此椭圆关于坐标轴与原点成轴对称与中心对称图形，所以点(2,3)关于坐标轴或原点的对称点均在椭圆上答案B答案B答案C答案2课堂典例讲练根据椭圆的方程研究几何性质分析由题目可获取以下主要信息：已知椭圆的方程；研究椭圆的几何性质解答本题可先把方程化成标准形式然后再写出性质方法规律总结由椭圆方程讨论其几何性质的步骤：(1)化椭圆方程为标准形式，确定焦点在哪个轴上(2)由标准形式求a、b、c，写出其几何性质利用椭圆的几何性质求标准方程求椭圆的离心率解析如图，连接BF2.答案B直线与椭圆的位置

3、关系答案2辨析上述解法没有讨论焦点的位置，而默认了椭圆的焦点在x轴上课课 时时 作作 业业（点此链接）（点此链接）团Tiffany，a 16yearold girl，was very shy.Last September，her best frien“I was really sad the moment I heard the bad news and I didnt know what to do，”Tiffany recalled.“I shut myself in my room for a whole week.It was then that my aunt took me to

4、a sports club one Saturday and I saw so many young people playing different kinds of sports there.I signed up for a beginners course in volleyball and since then I have been playing this sport.Now I practice twice a week there.It is wonderful playing sports in this club and I have made lots of frien

5、ds as well.2 ”The most basic aim of playing sports is that you can improve your health even if you are not very good at sports.Besides，you can get to know a circle of people at your age while playing sports.3 Since she joined the sports club，s I got used to the life here.And now I know lots of(5)_ h

6、ere.For example,when I meet my friend on the street,I usually(6)_ him like this,“Hey,where are you going?”In our country if someone asks this,people may get(7)_ but in this country people wont.Of course,there are some other interesting things here.Ill tell you about them next time.he has opened up h

7、erself and now she has become very active and enjoys meeting and talking with others.1Its polite for girls to kiss each other on the side of the face.s also become more confident.团圆圆一家在台湾可受欢迎了。每天，小朋友们排着长队，等着跟它们合影留念。从“排着长队”体现出每天喜欢它们的人不计其数，特别受选D.A.根据同类项合并法则,与不是同类项,不能合并,故本选项错误;B.根据算术平方根的定义,=3,故本选项错误;C.根据同底数幂的乘法aa2=a3,故本选项错误;D.根据积的乘方,(2a3)2=4a6,故本选项正确.欢迎。从“合影留念”体现出大家都想和大熊猫留住最美丽的瞬间以作纪念。Nothing can be accomplished without norms or standards.精品资料！感谢阅读下载！