£¨1£©É輯ºÏ £¬ £¬Ôò

£¨A£©{1,3}      £¨B£©{3,5}     £¨C£©{5,7}     £¨D£©{1,7}

£¨2£©Éè µÄʵ²¿ÓëÐ鲿ÏàµÈ£¬ÆäÖÐaΪʵÊý£¬Ôòa=

£¨A£©£­3     £¨B£©£­2     £¨C£©2      £¨D£©3

£¨3£©ÎªÃÀ»¯»·¾³£¬´Óºì¡¢»Æ¡¢°×¡¢×Ï4ÖÖÑÕÉ«µÄ»¨ÖÐÈÎÑ¡2ÖÖ»¨ÖÖÔÚÒ»¸ö»¨Ì³ÖУ¬ÓàϵÄ2ÖÖ»¨ÖÖÔÚÁíÒ»¸ö»¨Ì³ÖУ¬ÔòºìÉ«ºÍ×ÏÉ«µÄ»¨²»ÔÚͬһ»¨Ì³µÄ¸ÅÂÊÊÇ

£¨A£©       £¨B£©     £¨C£©        £¨D£©

£¨4£©¡÷ABCµÄÄÚ½ÇA¡¢B¡¢CµÄ¶Ô±ß·Ö±ðΪa¡¢b¡¢c.ÒÑÖª £¬ £¬ £¬Ôòb=

£¨A£©      £¨B£©    £¨C£©2         £¨D£©3

£¨5£©Ö±Ïßl¾­¹ýÍÖÔ²µÄÒ»¸ö¶¥µãºÍÒ»¸ö½¹µã£¬ÈôÍÖÔ²ÖÐÐĵ½lµÄ¾àÀëΪÆä¶ÌÖ᳤µÄ£¬Ôò¸ÃÍÖÔ²µÄÀëÐÄÂÊΪ

£¨A£©       £¨B£©     £¨C£©         £¨D£©