µÈ²îµÈ±ÈÊýÁеÄÐÔÖÊ×ܽá ÏÂÔØ±¾ÎÄ

½â£º£¨1£©ÓÉÒÑÖª¿ÉµÃa8??2£¬ËùÒÔa3?a13=2a8??4£¬S15=

15?a1?a15??15a8??30

2?a1?2?a1?64£¬ËùÒÔ»ò? aa?128,a?a?662ÓÉÌâ???1n1n?an?64?an?21a1?anq?q?2??q?ÓÖSn?»ò??126,ËùÒÔ?2

n?61?q???n?6?3?S99??a1?a4??a97???a2?a6??a98???a3?a6??a99??11???2??1??a3?a6?q??q?a99??a3?a6??a99?44

ÆÀ×¢£º·Ö½âÖØ×飬Òýµ¼·¢ÏÖ£¨a1?a4?ʹÎÊÌâ»ñµÃ¼òµ¥µÄ½â·¨¡£

¡¢£¨a2?a6??a97£©?a98£©Ó루a3?a6??a99£©µÄ¹ØÏµ£¬´Ó¶ø

?4?ÉèµÈ²îÊýÁй²2n-1Ïî,Ôò

SÆæSż?a1?a2n?1?n??a2?a2n?2?(n?1)22?n80??n?16 n?175ËùÒÔ´ËÊýÁй²31Ïî.ÖмäÏî?SÆæ?Sż?80?75?5

ÆÀ×¢£º£¨1£©ÔÚÏîÊýΪ2n?1ÏîµÄµÈ²îÊýÁÐ{an}ÖУ¬SÆæ=(n+1)aÖÐ,Sż=naÖÐ,S2n+1=(2n+1)aÖУ» £¨2£©ÔÚÏîÊýΪ2nÏîµÄµÈ²îÊýÁÐ{an}ÖÐSÆæ=nan,Sż=nan?1,S2n+1=n(an?an?1)£®

±äʽ£º£¨1£©ÈôÒ»¸öµÈ²îÊýÁÐǰ3ÏîµÄºÍΪ34£¬×îºóÈýÏîµÄºÍΪ146£¬ÇÒËùÓÐÏîµÄºÍΪ390,ÔòÕâ¸öÊýÁÐÓÐ13 Ï

£¨2£©ÒÑÖªÊýÁÐ{an}ÊǵȱÈÊýÁÐ,ÇÒan>0,n?N,a3a5?2a4a6?a5a7?81£¬Ôò

*a4?a6? 9 £®

£¨3£©µÈ²îÊýÁÐǰmÏîºÍÊÇ30£¬Ç°2mÏîºÍÊÇ100£¬ÔòËüµÄǰ3mÏîºÍÊÇ 210 £®

(4) µÈ²îÊýÁÐ{an}ºÍ{bn}µÄǰnÏîÖ®ºÍÖ®±ÈΪ(3n+1)£º(2n+3),Çó.Àý2¡¢ÉèµÈ²îÊýÁеÄǰnÏîÖ®ºÍΪSn£¬ÒÑÖªa3=12£¬S12>0£¬S13<0£¬

£¨1£©Ç󹫲îdµÄȡֵ·¶Î§¡£

£¨2£©Ö¸³öS1£¬S2£¬S3£¬¡­SnÖÐÄÄÒ»¸öÖµ×î´ó£¬²¢ËµÃ÷ÀíÓÉ¡£

a1588¡££¨=£©

61b15?2a?11d?012?1112?13d?0£¬S13?13a1?d?0£¬¼´?1£¬ 22?a1?6d?024?d??3¡£ ÓÉa3?a1?2d?12,´úÈëµÃ£º?7£¨2£©½âÒ»£ºÓÉS12?6?a6?a7??0£¬S13?13a7?0¿ÉÖªa6?0,a7?0£¬ËùÒÔS6×î´ó¡£

½â£º£¨1£©S12?12a1?½â¶þ£ºSn?24d2?5d??d??3¿ÉÖª£¬ËüµÄͼÏóÊÇ¿ª¿ÚÏòϵÄÅ×ÎïÏßÉϵÄһȺÀëÉ¢µÄn??12??n£¬ÓÉ?722??2µã£¬¸ù¾ÝͼÏó¿ÉÖªS6×î´ó¡£

24d?5d?24?d5d?242??d??3µÃ ½âÈý£ºSn??n?£¬ÓÉ?()?72?2d?22d5d?24136??¡£ÓÖÅ×ÎïÏß¿ª¿ÚÏòÏ£¬ËùÒÔS6×î´ó¡£

2d2ÆÀ×¢£ºÇóµÈ²îÊýÁÐSn×îÖµÓÐÈý·¨£º½èÖúÇóºÍ¹«Ê½ÊǹØÓÚnµÄ¶þ´Îº¯ÊýµÄÌØµã,ÓÃÅä·½·¨Çó½â;½èÖúµÈ²îÊýÁеÄ

ÐÔÖÊÅжÏ,ͨ¹ý¡±×ªÕÛÏÇó½â;½èÖú¶þ´Îº¯ÊýͼÏóÇó½â¡££¨¾­¹ýÔ­µã£©

±äʽ£º(1) ÒÑÖªµÈ²îÊýÁÐ{an}ÖУ¬a1?0,S5?S12£¬ÎÊS1£¬S2£¬S3£¬¡­SnÖÐÄÄÒ»¸öÖµ×î´ó¡£

- 5 -

(2) ÊýÁÐ{an}ÊÇÊ×ÏîΪ1000£¬¹«±ÈΪ

1µÄµÈ±ÈÊýÁУ¬ÊýÁÐ{bn}Âú×ã 101bk?(lga1?lga2?k?lgak)(k?N*)£¬

£¨1£©ÇóÊýÁÐ{bn}µÄǰnÏîºÍµÄ×î´óÖµ£»£¨2£©ÇóÊýÁÐ{|bn|}µÄǰnÏîºÍSn?£®

ÂԽ⣺£¨1£©ÓÉÌâµÃan?104?n£¬¡àlgan?4?n£¬¡à{lgan}ÊÇÊ×ÏîΪ3£¬¹«²îΪ?1µÄAP¡£

¡àlga1?lga2?k(k?1)1n(n?1)7?n]?£¬¡àbn?[3n?

2n22?bn?021ÓÉ?£¬µÃ6?n?7£¬¡àÊýÁÐ{bn}µÄǰnÏîºÍµÄ×î´óֵΪS6?S7?

2b?0?n?1?lgak?3k?£¨2£©ÓÉ£¨1£©µ±n?7ʱ£¬bn?0£¬µ±n?7ʱ£¬bn?0£¬

7?n2)n??1n2?13n ¡àµ±n?7ʱ£¬Sn??b1?b2??bn?(2441213µ±n?7ʱ£¬Sn??b1??b7?b8??bn?2S7?Sn?n?n?21

44?1213?n?n(n?7)??44¡àSn???£®

?1n2?13n?21(n?7)??44Àý3¡¢(1) ÓÉÕýÊý×é³ÉµÄµÈ±ÈÊýÁÐ{an}£¬Èôǰ2nÏîÖ®ºÍµÈÓÚËüǰ2nÏîÖеÄżÊýÏîÖ®ºÍµÄ11±¶£¬µÚ3ÏîÓëµÚ4

3?ÏîÖ®ºÍΪµÚ2ÏîÓëµÚ4ÏîÖ®»ýµÄ11±¶£¬ÇóÊýÁÐ{an}µÄͨÏʽ£®

?a1(1?q2n)11a1q(1?q2n)¢Ù

??1?q2½â£ºµ±q?1ʱ£¬µÃ2na1?11na1²»³ÉÁ¢£¬¡àq?1£¬¡à?1?q

?aq2?aq3?11aq?aq3¢Ú ?111111n?2ÓÉ¢ÙµÃq?£¬´úÈë¢ÚµÃa1?10£¬¡àan?()£®

1010˵Ã÷£ºÓõȱÈÊýÁÐǰnÏîºÍ¹«Ê½Ê±£¬Ò»¶¨Òª×¢ÒâÌÖÂÛ¹«±ÈÊÇ·ñΪ1£® (2) ÈôÊýÁÐ{an}³ÉµÈ²îÊýÁУ¬ÇÒSm?n,Sn?m(m?n)£¬ÇóSn?m£®

½â£º£¨·¨Ò»£©»ù±¾Á¿·¨£¨ÂÔ£©£»

2?(1)?An?Bn?m £¨·¨¶þ£©ÉèSn?An?Bn£¬Ôò? 2(2)??Am?Bm?n(1)?(2)µÃ£º(n2?m2)A?(n?m)B?m?n£¬m?n£¬ ¡à(m?n)A?B??1£¬

2¡àSn?m?(n?m)2A?(n?m)B??(n?m)£®

ÆÀ×¢£º·¨¶þץסÁ˵ȲîÊýÁÐǰnÏîºÍµÄÌØÕ÷Sn?An?Bn¡£

±äʽ£ºÉèÊýÁÐ{an}ΪµÈ²îÊýÁУ¬SnΪÊýÁÐ{an}µÄǰnÏîºÍ£¬ÒÑÖªS7=7£¬S15=75,TnΪÊýÁÐ{7?6?S?7a?d?71??72½â£º·¨Ò»£º£¨»ù±¾Á¿·¨£©Éè{an}Ê×ÏîΪa1£¬¹«²îΪd£¬Ôò?

15?14?S?15a?d?75151?2??a??2Sn(n?1)n?1n5¡à ?1 ¡à Sn??2?£¬¡à n??2???

d?12n222?2Sn}µÄǰnÏîºÍ£¬ÇóTn¡£ n- 6 -

¡à ´ËʽΪnµÄÒ»´Îº¯Êý£¬ ¡à {

Sn1a}ΪµÈ²îÊýÁУ¬¡à Tn?n2?n¡£

44n2

2??S7?A?7?7B?7·¨¶þ£º{an}ΪµÈ²îÊýÁУ¬ÉèSn=An+Bn£¬¡à ?

2??S15?A?15?15B?751?A??15?2 ¡à ½âÖ®µÃ£º?Sn?n2?n£¬ÏÂÂÔ¡£

22?B??5?2?

Àý4¡¢ÒÑÖªµÈ²îÊýÁÐ110,116,122,£¬

£¨1£©ÔÚÇø¼ä[450,600]ÉÏ£¬¸ÃÊýÁÐÓжàÉÙÏ²¢ÇóËüÃǵĺͣ»

£¨2£©ÔÚÇø¼ä[450,600]ÉÏ£¬¸ÃÊýÁÐÓжàÉÙÏîÄܱ»5Õû³ý£¿²¢ÇóËüÃǵĺÍ. ½â£ºan?110?6(n?1)?6n?104£¬

£¨1£©ÓÉ450?6n?104?600£¬µÃ58?n?82£¬ÓÖn?N,

*1(a58?a82)?25?13100£® 2£¨2£©¡ßan?110?6(n?1)£¬¡àҪʹanÄܱ»5Õû³ý£¬Ö»Òªn?1Äܱ»5Õû³ý£¬¼´n?1?5k£¬

¡à ¸ÃÊýÁÐÔÚ[450,600]ÉÏÓÐ25Ïî, ÆäºÍSn?¡àn?5k?1£¬¡à58?5k?1?82£¬¡à12?k?16£¬¡àÔÚÇø¼ä[450,600]ÉϸÃÊýÁÐÖÐÄܱ»5Õû³ýµÄÏî¹²ÓÐ5Ïî¼´µÚ61,66,71,76,81ÏÆäºÍS?5(a61?a81)?2650£®

2µÈ²î¡¢µÈ±ÈÊýÁÐÐÔÖʼ°Ó¦Óø´Ï°²Î¿¼Ìâ

Ò»¡¢Ñ¡ÔñÌâ

1.ÔÚÕýÕûÊý100ÖÁ500Ö®¼äÄܱ»11Õû³ýµÄ¸öÊýΪ£¨ £© A.34 B.35 C.36 D.37 2.{an}ÊǵȲîÊýÁУ¬ÇÒa1+a4+a7=45,a2+a5+a8=39,Ôòa3+a6+a9µÄÖµÊÇ£¨ £© A.24 B.27 C.30 D.33 3.É躯Êýf(x)Âú×ãf(n+1)=

A.95 B.97 C.105 D.192 4. Èô{an}ÊǵȲîÊýÁУ¬Ê×Ïîa1?0,a2003?a2004?0,a2003.a2004?0£¬ÔòʹǰnÏîºÍ

2f(n)?n(n¡ÊN*)ÇÒf(1)=2,Ôòf(20)Ϊ£¨ £© 2Sn?0³ÉÁ¢µÄ×î´ó×ÔÈ»ÊýnÊÇ£º

£¨ £©

A£®4005 B£®4006 C£®4007 D£®4008

5.µÈ²îÊýÁÐ{an}ÖУ¬ÒÑÖªa1=£­6,an=0,¹«²îd¡ÊN*,Ôòn(n¡Ý3)µÄ×î´óֵΪ£¨ £© A.5 B.6 C.7 D.8

6. ÉèÃüÌâ¼×:¡÷ABCµÄÒ»¸öÄÚ½ÇΪ60o£¬ÃüÌâÒÒ:¡÷ABCµÄÈý¸öÄڽǵĶÈÊý³ÉµÈ²îÊýÁÐ.ÄÇô( )

(A)¼×ÊÇÒҵijä·Ö²»±ØÒªÌõ¼þ (B)¼×ÊÇÒҵıØÒª²»³ä·ÖÌõ¼þ (C)¼×ÊÇÒҵijäÒªÌõ¼þ (D)¼×²»ÊÇÒҵijä·ÖÌõ¼þÒ²²»ÊÇÒҵıØÒªÌõ¼þ 7.ÒÑÖªµÈ²îÊýÁÐ{an}µÄ¹«²îΪÕýÊý£¬ÇÒa3¡¤a7=£­12,a4+a6=£­4,ÔòS20Ϊ£¨ £© A.180 B.£­180 C.90 D.£­90

8. ÏÖÓÐ200¸ùÏàͬµÄ¸Ö¹Ü£¬°ÑËüÃǶѷųÉÕýÈý½ÇÐζ⣬ҪʹʣÓàµÄ¸Ö¹Ü¾¡¿ÉÄܵÄÉÙ£¬ÄÇôʣÓà¸Ö¹ÜµÄ¸ùÊýΪ£¨ £© A.9 B.10 C.19 D.29

9.Óɹ«²îΪdµÄµÈ²îÊýÁÐa1¡¢a2¡¢a3¡­ÖØÐÂ×é³ÉµÄÊýÁÐa1+a4, a2+a5, a3+a6¡­ÊÇ£¨ £© A.¹«²îΪdµÄµÈ²îÊýÁÐ B.¹«²îΪ2dµÄµÈ²îÊýÁÐ

- 7 -

C.¹«²îΪ3dµÄµÈ²îÊýÁÐ D.·ÇµÈ²îÊýÁÐ

10.ÔڵȲîÊýÁÐ{an}ÖУ¬ÈôS9=18,Sn=240,an£­4=30,ÔònµÄֵΪ£¨ £© A.14 B.15 C.16 D.17 ¶þ¡¢Ìî¿ÕÌâ

2an211.ÔÚÊýÁÐ{an}ÖУ¬a1=1,an+1=(n¡ÊN*),ÔòÊÇÕâ¸öÊýÁеĵÚ_________Ïî.

an?2712.ÔڵȲîÊýÁÐ{an}ÖУ¬ÒÑÖªS100=10£¬S10=100£¬ÔòS110=_________.

13.ÔÚ£­9ºÍ3Ö®¼ä²åÈën¸öÊý£¬Ê¹Õân+2¸öÊý×é³ÉºÍΪ£­21µÄµÈ²îÊýÁУ¬Ôòn=_______.

Sa2n14.µÈ²îÊýÁÐ{an},{bn}µÄǰnÏîºÍ·Ö±ðΪSn¡¢Tn,Èôn=,Ôò11=_________.

Tn3n?1b1115. ÒÑÖªµÈ²îÊýÁÐ{a n}µÄ¹«²îd¡Ù0£¬ÇÒa1£¬a3£¬a9³ÉµÈ±ÈÊýÁУ¬Ôò16. ÈôÊýÁÐ{an}ÊǵȲîÊýÁУ¬ÔòÊýÁÐ?a1?a3?a9µÄÖµÊÇ

a2?a4?a10?a1?a2??an??ҲΪµÈ²îÊýÁУ¬Àà±ÈÉÏÊöÐÔÖÊ£¬ÏàÓ¦µØ£ºÈô{cn}n??ÊǵȱÈÊýÁУ¬ÇÒcn>0£¬Ôò{dn}ÊǵȱÈÊýÁÐ,ÆäÖÐdn? £®

17. Éèm¡ÊN+£¬log2mµÄÕûÊý²¿·ÖÓÃF(m)±íʾ£¬ÔòF(1)+F(2)+¡­+F(1024)µÄÖµÊÇ

Èý¡¢½â´ðÌ⣨±¾´óÌâ¹²5СÌ⣬¹²54·Ö.½â´ðӦд³öÎÄ×Ö˵Ã÷¡¢Ö¤Ã÷¹ý³Ì»òÑÝËã²½Ö裩 18.ÈôµÈ²îÊýÁÐ5£¬8£¬11£¬¡­Óë3£¬7£¬11£¬¡­¾ùÓÐ100ÏÎÊËüÃÇÓжàÉÙÏàͬµÄÏ

19. ÔڵȲîÊýÁÐ{an}ÖУ¬Èôa1=25ÇÒS9=S17,ÇóÊýÁÐǰ¶àÉÙÏîºÍ×î´ó.

20. ÒÑÖªf(x+1)=x2£­4,µÈ²îÊýÁÐ{an}ÖÐ,a1=f(x£­1), a2=£­

(1)ÇóxÖµ£» £¨2£©Çóa2+a5+a8+¡­+a26µÄÖµ.

21.ÒÑÖªÊýÁÐ{an}µÄǰnÏîºÍΪSn£¬ÇÒÂú×ãan+2Sn¡¤Sn£­1=0(n¡Ý2),a1=

3,a3=f(x). 21. 21}ÊǵȲîÊýÁУ» £¨2£©Çóan±í´ïʽ£» Sn£¨3£©Èôbn=2(1£­n)an(n¡Ý2),ÇóÖ¤£ºb22+b32+¡­+bn2<1.

(1)ÇóÖ¤£º{

- 8 -