2016-2017ѧÄê¸ßÖÐÊýѧ ½×¶ÎÖÊÁ¿¼ì²â(¶þ)ÐÂÈ˽ÌA°æÑ¡ÐÞ2-1

½âÎö£ºÓÉÅ×ÎïÏß¶¨ÒåÖª|PQ|£½x1£«x2£«p£½4p. ´ð°¸£º4p

13£®ÒÑÖªÍÖÔ²C£º£«£½1£¬µãMÓëCµÄ½¹µã²»Öغϣ®ÈôM¹ØÓÚCµÄ½¹µãµÄ¶Ô³Æµã·Ö±ð

94ΪA£¬B£¬Ïß¶ÎMNµÄÖеãÔÚCÉÏ£¬Ôò|AN|£«|BN|£½________.

½âÎö£ºÉèMN½»ÍÖÔ²ÓÚµãP£¬Á¬½ÓF1PºÍF2P(ÆäÖÐF1¡¢F2ÊÇÍÖÔ²CµÄ×ó¡¢ÓÒ½¹µã)£¬ÀûÓÃÖÐλÏß¶¨Àí¿ÉµÃ|AN|£«|BN|£½2|F1P|£«2|F2P|£½2¡Á2a£½4a£½12.

´ð°¸£º12

x2y2

x2y2

14£®·½³ÌΪ2£«2£½1(a£¾b£¾0)µÄÍÖÔ²µÄ×ó¶¥µãΪA£¬×ó¡¢ÓÒ½¹µã·Ö±ðΪF1¡¢F2£¬DÊÇËü

ab¨D¡ú¨D¡ú¨D¡ú

¶ÌÖáÉϵÄÒ»¸ö¶Ëµã£¬Èô3DF1£½DA£«2DF2£¬Ôò¸ÃÍÖÔ²µÄÀëÐÄÂÊΪ________£®

¨D¡ú¨D¡ú¨D¡ú

½âÎö£ºÉèµãD(0£¬b)£¬ÔòDF1£½(£­c£¬£­b)£¬DA£½(£­a£¬£­b)£¬DF2£½(c£¬£­b)£¬ÓɨD¡ú¨D¡ú¨D¡ú3DF1£½DA£«2DF2

1

µÃ£­3c£½£­a£«2c£¬¼´a£½5c£¬¹Êe£½.

51´ð°¸£º 5

Èý¡¢½â´ðÌâ(±¾Ìâ¹²6СÌ⣬¹²70·Ö£¬½â´ðʱӦд³öÎÄ×Ö˵Ã÷¡¢Ö¤Ã÷¹ý³Ì»òÑÝËã²½Öè) 4

15£®(±¾Ð¡ÌâÂú·Ö10·Ö)ÒÑ֪˫ÇúÏßÓëÍÖÔ²£«£½1¹²½¹µã£¬ÇÒÒÔy£½¡ÀxΪ½¥½üÏߣ®

49243(1)ÇóË«ÇúÏß·½³Ì£®

¦Ð

(2)Çó¹ýË«ÇúÏßÓÒ½¹µãÇÒÇãб½ÇΪµÄÖ±Ïß·½³Ì£®

3½â£º(1)ÍÖÔ²µÄ½¹µã×ø±êΪ(¡À5,0)£¬

x2y2

x2y2

ÉèË«ÇúÏß·½³ÌΪ2£­2£½1(a>0£¬b>0)£¬

abÔò½¥½üÏß·½³ÌΪ¡À£½0£¬¼´y£½¡Àx£¬

xyabbaa£«b£½25£¬??ËùÒÔ?b4

£½£¬??a3

??a£½9£¬

½âµÃ?2

??b£½16£¬

2

22

y2

ÔòË«ÇúÏß·½³ÌΪ£­£½1.

916

x2

¦Ð

(2)¡ßÖ±ÏßµÄÇãб½ÇΪ£¬

3¡àÖ±ÏßµÄбÂÊΪ3£¬ ¹ÊÖ±Ïß·½³ÌΪy£½3(x£­5)£¬ ¼´3x£­y£­53£½0.

16£®(±¾Ð¡ÌâÂú·Ö12·Ö)ÒÑÖªÍÖÔ²¡¢Å×ÎïÏß¡¢Ë«ÇúÏßµÄÀëÐÄÂʹ¹³ÉÒ»¸öµÈ±ÈÊýÁÐÇÒËüÃÇÓÐÒ»¸ö¹«¹²µÄ½¹µã(4,0)£¬ÆäÖÐË«ÇúÏßµÄÒ»Ìõ½¥½üÏß·½³ÌΪy£½3x£¬ÇóÈýÌõÇúÏߵıê×¼·½³Ì£®

½â£ºÒòΪ˫ÇúÏߵĽ¹µãÔÚxÖáÉÏ£¬

x2y2

¹ÊÆä·½³Ì¿ÉÉèΪ2£­2£½1(a>0£¬b>0)£¬

abÓÖÒòΪËüµÄÒ»Ìõ½¥½üÏß·½³ÌΪy£½3x£¬

bËùÒÔ£½3£¬¼´

ab2£½a2c2£­a22

£½e£­1£½3. 2

a½âµÃe£½2£¬ÒòΪc£½4£¬ ËùÒÔa£½2£¬b£½3a£½23£¬ ËùÒÔË«ÇúÏß·½³ÌΪ£­£½1.

412

ÒòΪÍÖÔ²¡¢Å×ÎïÏß¡¢Ë«ÇúÏßµÄÀëÐÄÂʹ¹³ÉÒ»¸öµÈ±ÈÊýÁУ¬ËùÒÔÕâ¸öµÈ±ÈÊýÁеÄÖмäÏîÒ»¶¨ÊÇÅ×ÎïÏßµÄÀëÐÄÂÊ1£¬

ÓɵȱÈÊýÁÐÐÔÖʿɵÃÍÖÔ²ºÍË«ÇúÏßµÄÀëÐÄÂÊ»¥Îªµ¹Êý£¬ 1

Òò´Ë£¬ÍÖÔ²µÄÀëÐÄÂÊΪ£¬

2

x2y2

x2y2

ÉèÍÖÔ²·½³ÌΪ2£«2£½1(a1>b1>0)£¬

a1b1

Ôòc£½4£¬a1£½8£¬b1£½8£­4£½48. ËùÒÔÍÖÔ²µÄ·½³ÌΪ£«£½1.

6448Ò×ÖªÅ×ÎïÏߵķ½³ÌΪy£½16x.

17£®(±¾Ð¡ÌâÂú·Ö12·Ö)¶¥µãÔÚÔ­µã£¬½¹µãÔÚyÖáµÄÕý°ëÖáµÄÅ×ÎïÏߵĽ¹µãµ½×¼ÏߵľàÀëΪ2.

(1)ÇóÅ×ÎïÏߵıê×¼·½³Ì£»

(2)ÈôÖ±Ïßl£ºy£½2x£«1ÓëÅ×ÎïÏßÏཻÓÚA£¬BÁ½µã£¬ÇóABµÄ³¤¶È£® ½â£º(1)ÓÉÌâÒâ¿ÉÖªp£½2£¬¡àÅ×ÎïÏß±ê×¼·½³ÌΪx£½4y.

(2)Ö±Ïßl£ºy£½2x£«1¹ýÅ×ÎïÏߵĽ¹µãF(0,1)£¬ÉèA(x1£¬y1)£¬B(x2£¬y2)£¬

2

2

2

2

2

x2y2

??y£½2x£«1£¬

¡à|AB|£½y1£«y2£«p£½y1£«y2£«2£¬ÁªÁ¢?2

?x£½4y?

µÃx£­8x£­4£½0£¬

2

¡àx1£«x2£½8£¬

¡à|AB|£½y1£«y2£«2£½2x1£«1£«2x2£«1£«2£½2(x1£«x2)£«4£½20.

x2y2

18£®(±¾Ð¡ÌâÂú·Ö12·Ö)ÒÑÖªF1£¬F2ÊÇÍÖÔ²2£«2£½1(a£¾b£¾0)µÄÁ½¸ö½¹µã£¬OÎª×ø±êÔ­

abµã£¬µãP?£­1£¬?2?¨D¡ú

?ÔÚÍÖÔ²ÉÏ£¬ÇÒPF1¡¤F1F2¨D¡ú£½0£¬¡ÑOÊÇÒÔF1F2Ϊֱ¾¶µÄÔ²£¬Ö±Ïßl£ºy?2?

£½kx£«mÓë¡ÑOÏàÇУ¬²¢ÇÒÓëÍÖÔ²½»ÓÚ²»Í¬µÄÁ½µãA£¬B.

(1)ÇóÍÖÔ²µÄ±ê×¼·½³Ì£»

(2)µ±¨DOA¡ú¡¤¨DOB¡ú£½2

3ʱ£¬ÇókµÄÖµ£®

½â£º(1)ÒÀÌâÒ⣬¿ÉÖªPF1¡ÍF1F2£¬ ¡àc£½1£¬11222

a2£«2b2£½1£¬a£½b£«c£¬

½âµÃa2

£½2£¬b2

£½1£¬c2

£½1£¬ ¡àÍÖÔ²µÄ±ê×¼·½³ÌΪx2

2

2

£«y£½1.

(2)Ö±Ïßl£ºy£½kx£«mÓë¡ÑO£ºx2

£«y2

£½1ÏàÇУ¬ Ôò

|m|

2

£½1£¬¼´22

k£«1

m£½k£«1. ?x2

ÓÉ??2£«y2£½1£¬??y£½kx£«m£¬

µÃ(1£«2k2

)x2

£«4kmx£«2m2

£­2£½0. ¡ßÖ±ÏßlÓëÍÖÔ²½»ÓÚ²»Í¬µÄÁ½µãA£¬B£¬ ÉèA(x1£¬y1)£¬B(x2£¬y2)£¬ ¡à¦¤£¾0?k2

£¾0?k¡Ù0£¬ 2

x4km2m£­21£«x2£½£­1£«2k2£¬x1x2£½1£«2k2£¬

y)£½k2

x2

m2£­2k21£­k2

1y2£½(kx1£«m)(kx2£«m1x2£«km(x1£«x2)£«m£½1£«2k2£½1£«2k2£¬

2

¡à¨DOA¡ú¡¤¨DOB¡ú

£½x1£«k21x2£«y1y2£½1£«2k2£½3

£¬¡àk£½¡À1.

19£®(±¾Ð¡ÌâÂú·Ö12·Ö)ÉèF1£¬F2·Ö±ðÊÇÍÖÔ²x2

£«y2

4

£½1µÄ×ó¡¢ÓÒ½¹µã£®

5¨D¡ú¨D¡ú

(1)ÈôPÊǵÚÒ»ÏóÏÞÄÚ¸ÃÍÖÔ²ÉϵÄÒ»µã£¬ÇÒPF1¡¤PF2£½£­£¬ÇóµãPµÄ×ø±ê£»

4(2)Éè¹ý¶¨µãM(0,2)µÄÖ±ÏßlÓëÍÖÔ²½»ÓÚ²»Í¬µÄÁ½µãA£¬B£¬ÇÒ¡ÏAOBΪÈñ½Ç(ÆäÖÐOÎª×ø±êÔ­µã)£¬ÇóÖ±ÏßlµÄбÂÊkµÄȡֵ·¶Î§£®

½â£º(1)ÉèP(x£¬y)£¬ 4??Ôò?x£«3x£­??x£¾0£¬y£¾0£¬

£«y£½1£¬

2

x2

3

52

£«y£½£­£¬4

x£½1£¬??½âµÃ?3

y£½£¬?2?

¹ÊP?1£¬

?

?3??. 2?

(2)ÓÉÌâÒâÖªÖ±ÏßlµÄбÂÊ´æÔÚ£¬ËùÒÔ¿ÉÉèÖ±ÏßlµÄ·½³ÌΪy£½kx£«2£¬½«Æä´úÈëÍÖÔ²·½³Ì£¬

3222

µÃ(1£«4k)x£«16kx£«12£½0£¬¦¤£¾0?k£¾.

416kÉèA(x1£¬y1)£¬B(x2£¬y2)£¬Ôòx1£«x2£½£­2£¬

1£«4kx1x2£½

12

2. 1£«4k¨D¡ú¨D¡ú2

ÓÉ¡ÏAOBΪÈñ½Ç¿ÉµÃ£¬OA¡¤OB£¾0?x1x2£«y1y2£¾0?(1£«k)x1x2£«2k(x1£«x2)£«4£¾0£¬ 1216k3??22

¼´(1£«k)¡¤½âµÃk£¼4£¬×ÛÉÏ£¬kµÄȡֵ·¶Î§Îª?£­2£¬£­?2£­2k¡¤2£«4£¾0£¬

1£«4k1£«4k2??¡È?

?3?

£¬2?. ?2?

3??1£¬20£®(±¾Ð¡ÌâÂú·Ö12·Ö)ÒÑÖªF1¡¢F2ΪÍÖÔ²EµÄ×ó¡¢ÓÒ½¹µã£¬µãP??ΪÆäÉÏÒ»µã£¬ÇÒ

?2?

ÓÐ|PF1|£«|PF2|£½4.

(1)ÇóÍÖÔ²CµÄ±ê×¼·½³Ì£»

(2)¹ýF1µÄÖ±Ïßl1ÓëÍÖÔ²E½»ÓÚA¡¢BÁ½µã£¬¹ýF2Óël1ƽÐеÄÖ±Ïßl2ÓëÍÖÔ²E½»ÓÚC¡¢DÁ½µã£¬ÇóËıßÐÎABCDµÄÃæ»ýSËıßÐÎABCDµÄ×î´óÖµ£®

x2y2

½â£º(1)ÉèÍÖÔ²EµÄ±ê×¼·½³ÌΪ2£«2£½1(a>b>0)£¬

abÓÉÒÑÖª|PF1|£«|PF2|£½4µÃ2a£½4£¬¡àa£½2£¬

ÁªÏµ¿Í·þ£º779662525#qq.com(#Ìæ»»Îª@)