2021年关于高二数学数列教案.pdf

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1、2.1 数列一：教学目标：1、知道数列的概念，了解数列的分类，理解数列是一种特殊的函数，会用列表法和图象法表示数列。2、理解数列通项公式的概念，会根据通项公式写出数列的前几项，会根据简单数列的前几项写出数列的通项公式。二：教学重点：1、数列的概念及数列与集合的区别2、数列与函数的关系3、归纳数列的通项公式三：教学过程：一、问题情境（1）填数：2，4，6，10；（2）n)1(：-1，1，-1，1，（3）细胞分裂：1，2，4，8，16，632（象棋中放米粒）（4）斐波那契数列：1，1，2，3，5，8，13，（5）奥运会金牌数：（1984-2004）15，5，16，16，28，32 问：上面这些例子

2、有什么共同的特点？二、学生活动:通过观察发现：1、每一个问题里都有一系列的数2、这些数有一定的次序，前后位置不能颠倒，并且有些数可以相同，但表示不同的意义。通过讨论，得到这些情景的共同特点是都有一组按照一定次序排列的数。三：数学建构1、数列：按照一定次序排列的一列数与集合比较：（1）有序；（2）不互异2、数列的项：数列中的每个数用小写的英文字母：,.,.,321naaaa简记为na第 1 项（首项），第 n 项3、数列与函数的关系：（1）定义域：*N（或它的有限子集n,.2,1）（2）自变量由小到大依次取值（3）函数值4、数列的通项公式：数列na的第 n 项与序号 n 之间的关系可用一个公式来

3、表示（1）作用：给出一个数列（1）nan2数列简记为12,2nn所有奇数前 5 项（2）nna)1(（3）nna2（2）不是每个数列都能写出它的通项公式；有的数列虽然有通项公式，但形式不唯一；仅仅知道一个数列的前面的有限项，无其他说明，数列是不能确定的四：数学运用例 1：根据下面数列的前几项的值，写出数列的一个通项公式.文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1

4、A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 H

5、R7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X

6、7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3

7、ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W

8、3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文

9、档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB

10、4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P81111,1 223 3 44 5L0,2,0,2,L摆动数列练：（1,2,1,2,L）1 4 9 16,3 5 79L1 111,3 815 24L1 1 3 15,2 2 8 4 32L3 1311,5 3 17 11L9,99,999,9999,L练：（1,11,111,1111,L）0.7,0.77,0.777,0.7777,L解：111nnan n11nna221nnan221111211nnnannn1 2 3 45,2 4 8

11、16 32L3 3 333,3 5 9 17 33L101nna练：11019nna770.9,0.99,99L5数列的表示方法：函数、列表法、图象法，解析法通项公式例 2：数列na的通项公式是：254nann，文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7

12、T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 Z

13、P5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3

14、L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档

15、编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4

16、M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A

17、7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR

18、7Z10X7T5P3 ZP5B2W3L3P8做出图象；数列中有多少项是负数？n为何值时，na有最小值？并求出最小值.6数列的分类：恒成立例 3：已知数列na的通项公式为nanabnc，其中,a b c均为正数，比较na与1na的大小.解：()1aacbbnbncanaacabncbncbbbnc增练：9899nnan最大项是，最小项是 .五：回顾小结1、数列的概念及分类，数列和函数的关系2、数列的通项公式六：课外作业1、课后练习 5，6 2、习题 1，2，3，4，5，6 2.2.1 等差数列教学目标1 明确等差数列的定义2 能用定义判断一个数列是否为等差数列.3 掌握等差数列的通项公式，了解等

19、差数列通项公式的推导过程及思想，并能在解题中加以利用.文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7

20、Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T

21、5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP

22、5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L

23、3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编

24、码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M

25、10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8教学重点1等差数列的概念；2等差数列通项公式的推导及应用.教学难点理解等差数列“等差”的特点及通项公式的含义.教学

26、方法启发式数学教具准备多媒体 ppt(内容见下面)教学过程上两节课我们共同学习了数列的定义及给出数列的两种方法通项公式和递推公式.这两个公式从不同的角度反映数列的特点.一、问题情境（1）影院双号的座位号为：2，4，6，8，10，12；（2）小明觉得自己的英语很好，单词量3000，今天起不背单词，每天忘掉5个，依次为：3000，2995，2990，2985，2980；（3）1986 年，人类在地球上观测到哈雷慧星第5 次出现，最早在1682 年，每隔 76 年观测到一次，依次为：1682，1758，1834，1910，1986，2062.二、学生活动请大家观察以上三个数列，看看这三个数列有什么共

27、同特点？生：这些数列后一项与前一项之差是常数，分别是2、5、76.三、建构数学文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M

28、10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7

29、C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7

30、Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T

31、5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP

32、5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L

33、3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8等差数列：一般地，如果一个数列从第2 项起，每一项与前一项的差等于同一个常数，那么这个数列

34、就叫做等差数列，这个常数叫做等差数列的公差，通常用字母 d 表示.na是等差数列daann 1（常数）练习 1 下列数列是否是等差数列：(1)3,7,11,15,19,23(2)1,2,4,6,8,10,12(3)3,3,3,3,3,3,3(4)5,0,5,0,5,0,5(5)8,6,5,2,0,-2,-4 归纳：()公差d是由后项减前项所得，而不仅仅是前后两项的差；()对数列na，若)(1Nndaann，则na是等差数列，其中d为公差.练习 2 求证数列na：)(9lg3lg411Nnannn是等差数列.分析：要证一个数列是等差数列，根据等差数列的定义，只要证nnaa1是一个与n无关的常数.

35、证明：由题可知：3lg)22(9lg3lg4111nannn常数3lg23lg)22(3lg2)1(21nnaann 数列na是等差数列推导：等差数列的通项公式法一：累加法等差数列na的首项是1a，公差是d文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P

36、3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B

37、2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P

38、8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:

39、CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10

40、A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1

41、 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z1

42、0X7T5P3 ZP5B2W3L3P8dnaan)1(1)2(n当1n时，左式1a，右式1a，即1n时，等式也成立dnaan)1(1 (Nn)法二：递推法（不完全归纳法）上式对1n亦成立)()1(1Nndnaan口答：求引例的通项公式（学生）根据等差数列的通项公式，再nanda,1这四个量中，只要知道其中任意三个量，就可求出另一个量.（知三求一）四：数学运用例 1(1)求等差数列,16,24,32的第 20 项解：dnaa)1(1404020820a (2)404是不是等差数列,19,14,9的项？分析：要判断404是不是该数列的项，关键式求出数列的通项公式na，看是否存在正整数n，使得401

43、na成立解：dnaan)1(1令45404n得80n即404是该数列得第80项练习 2.在等差数列na中，已知105a，3112a，求18a解：311110411dada321da53)1(32)1(1nndnaan49518318a文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7

44、C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7

45、Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T

46、5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP

47、5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L

48、3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编

49、码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8文档编码:CB4M

50、10A1A7C1 HR7Z10X7T5P3 ZP5B2W3L3P8思考：能否不求da,1，而利用等差数列项与项之间的关系求解？猜想：dmnaamn)(证明：dnaadnaamn)1()1(11故dndmaamn)1()1(49363112181218daa五、回顾小结：1.等差数列的概念；2用定义法判断数列是否为等差数列；3等差数列通项公式的推导及应用.六、课外作业1、课后练习及数学之友2.2.2等差数列的通项公式教学目的：1理解等差中项的概念，会求两个数的等差中项；2初步掌握从等差数列中项的序号关系推断序号对应的项的关系；3会用等差中项等性质解决简单问题。教学重点：等差数列的性质教学过程：一