《2022年数学归纳法海选专题 .pdf》由会员分享,可在线阅读,更多相关《2022年数学归纳法海选专题 .pdf(7页珍藏版)》请在taowenge.com淘文阁网|工程机械CAD图纸|机械工程制图|CAD装配图下载|SolidWorks_CaTia_CAD_UG_PROE_设计图分享下载上搜索。
1、数学归纳法海选专题证明一些等式和不等式注意:(1)初始值(2)由 n=k 到 n=k+1 时注意增加的项数一定要用n=k 正确这个结论(3)特殊猜想证明(4))1(11)1(12nnnnn一 用数学归纳法证明等式:1.用数学归纳法证明nnnnn2121112112141312112、用数学归纳法证明:123234 n(n 1)(n2)n n1 n2 n34(nN*)二用数学归纳法证明下述不等式:1.用数学归纳法证明11112()23n nNn2.设*,0Nnx且2n,求证:nxxn11.三整除问题:1.试证当 n 为自然数时,f(n)32n28n9 能被 64 整除2.若 5n23n1 1(n
2、N*)能被正整数m 整除,请写出m 的最大值,并给予证明解:当 n1 时,5123018,m8,(2 分)下证 5n23n11(nN*)能被 8 整除(3 分)当 n1 时已证;(4 分)假设当 nk(kN*)时命题成立,即5k23k11 能被 8整除(5 分)则当 nk 1 时,5k123k 15 5k6 3k11(6 分)(5k23k11)4(5k3k1),(7 分)5k23k11 能被 8整除,而5k3k1为偶数,4(5k3k 1)也能被 8 整除,即当nk1 时命题也成立(8 分)3.用数学归纳法证明:*21Nnxn能被1x整除.四与数列有关问题:1已知正项数列na中,对于一切的*nN
3、均有21nnnaaa成立。(1)证明:数列na中的任意一项都小于1;(2)探究na与1n的大小,并证明你的结论.1解:(1)由21nnnaaa得21nnnaaa在数列na中0na,10na,20,01nnnaaa故数列na中的任意一项都小于1.(2)由(1)知1011na,那么2221111111()2442aaaa,由此猜想:1nan(n2).下面用数学归纳法证明:当 n=2 时,显然成立;当 n=k 时(k2,k N)时,假设猜想正确,即112kak,那么22212221111111111()()242411kkkkkkaaaakkkkkk,当 n=k+1 时,猜想也正确综上所述,对于一切
4、*nN,都有1nan。2.已知数列na的前n项和为nS,通项公式为1nan,2211()2nnnSnf nSSn,(1)计算(1),(2),(3)fff的值;(2)比较()f n与 1 的大小,并用数学归纳法证明你的结论.解:(1)由已知213(1)122fS,4111113(2)23412fSS,62111119(3)345620fSS;(2)由()知(1)1,(2)1ff;下面用数学归纳法证明:当3n时,()1f n()由()当3n时,()1f n;()假设(3)nk k时,()1f k,即111()112f kkkk,那么11111(1)1222122f kkkkkk1111111122
5、2122kkkkkkk11111212222kkkk2(21)2(22)12(21)2(22)kkkkkkkk11112(21)(22)kkkk,所以当1nk时,()1f n也成立由(1)和(2)知,当3n时,()1f n所以当1n,和2n时,()1f n;当3n时,()1f n文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9
6、Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I
7、10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码
8、:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1
9、Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9
10、 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2
11、H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2
12、 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I103.已知数列na中,112a,21112nnnaaa(*)nN(1)求证:311 3(,)8 2a;(2)求证:当3n时,1|2|2nna解:(1)因为112a,所以22211111331(1)(1,)2222aaaa2分故22322211311 31(1)(,)2228 2aaaa4 分(2)当3n时,31132(2,2)82a,又111 312,288 28,所以311288a,即31|2|8a6 分假设当(3)nk k时,1|2|2kka则当1nk时,11|2|2|22|2kk
13、kaaa8 分111|222|222kk112k10 分即1nk时结论成立综上所述,当3n时,1|2|2nna4、已知正项数列na中,111,1()1nnnaaanNa。用数学归纳法证明:1()nnaanN。答案要点:当1n时,1213112aaa,12aa,所以,1n时,不等式成立;假设nk(*kN)时,1kkaa成立,则当1nk时,112111111(1)111kkkkkkkkkaaaaaaaaa11111kkaa110(1)(1)kkkkaaaa,文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2
14、ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z
15、10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I1
16、0文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:
17、CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y
18、5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9
19、HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H
20、5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10所以,1nk时,不等式成立综上所述,不等式1()nnaanN成立5、已知数列na满足11a,且11429nnnnaa aa(nN)(1)求123,a aa的值(2)由(1)猜想na的通项公式,并给出证明。解:(1)由11429nnnnaa aa得1921244nnnnaaaa,求得23471319,357aa
21、a 3 分(2)猜想6521nnan 5分证明:当n=1 时,猜想成立。6 分设当 n=k 时()kN时,猜想成立,即6521kkak,7 分则当 n=k+1 时,有111616(1)522654212(1)1421kkkkakakkk,所以当 n=k+1 时猜想也成立 9 分综合,猜想对任何nN都成立。10 分6、已知数列na中,an=n(n+1)(n+2).又 Sn=kn(n+1)(n+2)(n+3),试确定常数k,使 S n恰为na的前 n 项的和,并用数学归纳法证明你的结论.解:由 a1=S1,k=14.下面用数学归纳法进行证明.1.当 n=1 时,命题显然成立;2.假设当 n=k(k
22、N*)时,命题成立,即 123+234+k(k+1)(k+2)=14k(k+1)(k+2)(k+3),则 n=k+1 时,123+234+k(k+1)(k+2)+(k+1)(k+2)(k+3)=14k(k+1)(k+2)(k+3)+(k+1)(k+2)(k+3)=14(k+1)(k+1+1)(k+1+2)(k+1+3)即命题对n=k+1.成立由 1,2,命题对任意的正整数n 成立.7 已 知 正 项 数 列na中,111,1()1nnnaaanNa。用 数 学 归 纳 法 证 明:文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X
23、9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P
24、2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O
25、2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J
26、9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3
27、I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编
28、码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W
29、1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I101()nnaanN。8.已知数列na的各项都是正数且满足)4(21,110nnnaaaaNn(1)求21,aa(2)证明:21nnaa9、已知数列na满足*1121,232nnnaanaaN()计算234,a a a;()猜想数列的通项na,并利用数学归纳法证明解:()由递推公式,
30、得121122321234232aaa,3457,68aa 3 分()猜想:212nnan5 分证明:1n时,由已知,等式成立6 分设*()nk kN时,等式成立即212kkak7 分所以12122214212(1)122123426222(1)232kkkkakkkkkakakkkkk,所以1nk时,等式成立9 分根据可知,对任意*nN,等式成立即通项212nnan 10 分五与几何知识有关问题:1.空间内有*Nnn个不重合的平面,设这n个平面最多将空间分成na*Nn个部分.(1)求;,4321aaaa(2)写出na 关于*Nnn的表达式,并用数学归纳法证明.2.平面上有n 个圆,每两个圆交
31、于两点,每三个圆不过同一点,求证这n 个圆分平面为n2n2 个部分文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X
32、9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P
33、2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O
34、2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J
35、9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3
36、I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编
37、码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I103.n 个半圆的圆心在同一条直线l 上,这 n 个半圆每两个都相交,且都在直线l 的同侧,问这些半圆被
38、所有的交点最多分成多少段圆弧?分析:设这些半圆最多互相分成f(n)段圆弧,采用由特殊到一般的方法,进行猜想和论证当 n=2 时,由图(1)两个半圆交于一点,则分成4 段圆弧,故f(2)=4=22当 n=3 时,由图(2)三个半径交于三点,则分成9 段圆弧,故f(3)=9=32由 n=4 时,由图(3)三个半圆交于6 点,则分成16 段圆弧,故 f(4)=16=42由此猜想满足条件的n 个半圆互相分成圆弧段有f(n)=n2用数学归纳法证明如下:当 n=2 时,上面已证设 n=k 时,f(k)=k2,那么当 n=k+1 时,第 k+1 个半圆与原k 个半圆均相交,为获得最多圆弧,任意三个半圆不能交
39、于一点,所以第k+1 个半圆把原k 个半圆中的每一个半圆中的一段弧分成两段弧,这样就多出 k条圆弧;另外原k 个半圆把第k+1 个半圆分成k+1 段,这样又多出了k+1 段圆弧 f(k+1)=k2+k+(k+1)=k2+2k+1=(k+1)2 满足条件的k+1 个半圆被所有的交点最多分成(k+1)2段圆弧由、可知,满足条件的n 个半圆被所有的交点最多分成n2段圆弧说明:这里要注意;增加一个半圆时,圆弧段增加了多少条?可以从f(2)=4,f(3)=f(2)+2+3,f(4)=f(3)+3+4 中发现规律:f(k+1)=f(k)+k+(k+1)4.用,a b c d四个不同字母组成一个含1n*)(
40、Nn个字母的字符串,要求由a开始,相邻两个字母不同.例如1n时,排出的字符串是,ab ac ad;2n时排出的字符串是,aba abc abd aca acb acd ada adb adc,如图所示.记这含1n个字母的所有字符串中,排在最后一个的字母仍是a的字符串的种数为na.试用数学归纳法证明:*33(1)(N,1)4nnnann;a b c d n=1a b c d n=2a c d a b d a b c 文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP
41、1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D
42、8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB
43、8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W
44、1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ
45、8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10
46、D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文
47、档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10解(1):证明:()当1n时,因为10a,33(1)04,所以等式正确.()假设nk时,等式正确,即*33(1)(N,1)4kkkakk,那么,1nk时,因为11133(1)4 333(1)33(1)33444kkkkkkkkkkkaa,这说明1nk时等式仍正确.据(),()可知,*33(1)(N,1)4nnnann正确.-10分文档编码:CP1W
48、1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X
49、9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P
50、2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O2 ZJ8J9Z10D3I10文档编码:CP1W1Y5D8X9 HB8P2H5W1O