ÌâÄ¿ÄÚÈÝ
(±¾Ð¡ÌâÂú·Ö16·Ö)¼Ç¹«²îd¡Ù0µÄµÈ²îÊýÁÐ{an}µÄÇ°nÏîºÍΪSn£¬ÒÑÖªa1£½2£«£¬S3£½12£«£®
£¨1£©ÇóÊýÁÐ{an}µÄͨÏʽan¼°Ç°nÏîºÍSn£»
£¨2£©¼Çbn£½an££¬Èô×ÔÈ»Êýn1£¬n2£¬¡£¬nk£¬¡Âú×ã1¡Ün1£¼n2£¼¡£¼nk£¼¡£¬²¢ÇÒ£¬£¬¡£¬£¬¡³ÉµÈ±ÈÊýÁУ¬ÆäÖÐn1£½1£¬n2£½3£¬Çónk£¨ÓÃk±íʾ£©£»
£¨3£©ÊÔÎÊ£ºÔÚÊýÁÐ{an}ÖÐÊÇ·ñ´æÔÚÈýÏîar£¬as£¬at(r£¼s£¼t£¬r£¬s£¬t¡ÊN*)Ç¡ºÃ³ÉµÈ±ÈÊýÁУ¿Èô´æÔÚ£¬Çó³ö´ËÈýÏÈô²»´æÔÚ£¬Çë˵Ã÷ÀíÓÉ£®
£¨1£©ÇóÊýÁÐ{an}µÄͨÏʽan¼°Ç°nÏîºÍSn£»
£¨2£©¼Çbn£½an££¬Èô×ÔÈ»Êýn1£¬n2£¬¡£¬nk£¬¡Âú×ã1¡Ün1£¼n2£¼¡£¼nk£¼¡£¬²¢ÇÒ£¬£¬¡£¬£¬¡³ÉµÈ±ÈÊýÁУ¬ÆäÖÐn1£½1£¬n2£½3£¬Çónk£¨ÓÃk±íʾ£©£»
£¨3£©ÊÔÎÊ£ºÔÚÊýÁÐ{an}ÖÐÊÇ·ñ´æÔÚÈýÏîar£¬as£¬at(r£¼s£¼t£¬r£¬s£¬t¡ÊN*)Ç¡ºÃ³ÉµÈ±ÈÊýÁУ¿Èô´æÔÚ£¬Çó³ö´ËÈýÏÈô²»´æÔÚ£¬Çë˵Ã÷ÀíÓÉ£®
£¨1£©ÒòΪa1£½2£«£¬S3£½3a1£«3d£½12£«£¬ËùÒÔd£½2£®
ËùÒÔan£½a1£«(n£1)d£½2n£«£¬ Sn£½£½n2£«(£«1)n£®
£¨2£©ÒòΪbn£½an££½2n£¬ËùÒÔ£½2nk£®ÓÖÒòΪÊýÁÐ{}µÄÊ×Ï£¬
¹«±È£¬ËùÒÔ£®ËùÒÔ2nk£¬¼´nk£®
£¨3£©¼ÙÉè´æÔÚÈýÏîar£¬as£¬at³ÉµÈ±ÈÊýÁУ¬Ôò£¬
¼´ÓУ¬ÕûÀíµÃ£®
Èô£¬Ôò£¬ÒòΪr£¬s£¬t¡ÊN*£¬ËùÒÔÊÇÓÐÀíÊý£¬
ÕâÓëΪÎÞÀíÊýì¶Ü£»
Èô£¬Ôò£¬´Ó¶ø¿ÉµÃr£½s£½t£¬ÕâÓër£¼s£¼tì¶Ü£®
×ÛÉÏ¿ÉÖª£¬²»´æÔÚÂú×ãÌâÒâµÄÈýÏîar£¬as£¬at£®
ËùÒÔan£½a1£«(n£1)d£½2n£«£¬ Sn£½£½n2£«(£«1)n£®
£¨2£©ÒòΪbn£½an££½2n£¬ËùÒÔ£½2nk£®ÓÖÒòΪÊýÁÐ{}µÄÊ×Ï£¬
¹«±È£¬ËùÒÔ£®ËùÒÔ2nk£¬¼´nk£®
£¨3£©¼ÙÉè´æÔÚÈýÏîar£¬as£¬at³ÉµÈ±ÈÊýÁУ¬Ôò£¬
¼´ÓУ¬ÕûÀíµÃ£®
Èô£¬Ôò£¬ÒòΪr£¬s£¬t¡ÊN*£¬ËùÒÔÊÇÓÐÀíÊý£¬
ÕâÓëΪÎÞÀíÊýì¶Ü£»
Èô£¬Ôò£¬´Ó¶ø¿ÉµÃr£½s£½t£¬ÕâÓër£¼s£¼tì¶Ü£®
×ÛÉÏ¿ÉÖª£¬²»´æÔÚÂú×ãÌâÒâµÄÈýÏîar£¬as£¬at£®
ÂÔ
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿