ÌâÄ¿ÄÚÈÝ
£¨±¾ÌâÂú·Ö14·Ö µÚ£¨1£©Ð¡Ìâ4·Ö£¬µÚ£¨2£©Ð¡Ìâ4·Ö£¬µÚ£¨3£©Ð¡Ìâ6·Ö£©
ÒÑÖª£ºÈçͼ£¬ÔÚ¡÷ABCÖУ¬AB£½AC£½15£¬ cos¡ÏA£½£®µãMÔÚAB±ßÉÏ£¬AM£½2MB£¬µãPÊDZßACÉϵÄÒ»¸ö¶¯µã£¬ÉèPA£½x£®
£¨1£©Çóµ×±ßBCµÄ³¤£»
£¨2£©ÈôµãOÊÇBCµÄÖе㣬Áª½ÓMP¡¢MO¡¢OP£¬ÉèËıßÐÎAMOPµÄÃæ»ýÊÇy£¬Çóy¹ØÓÚxµÄº¯Êý¹Øϵʽ£¬²¢³öд³öxµÄÈ¡Öµ·¶Î§£»
£¨3£©°Ñ¡÷MPAÑØ×ÅÖ±ÏßMP·ÕÛºóµÃµ½¡÷MPN£¬ÊÇ·ñ¿ÉÄÜʹ¡÷MPNµÄÒ»Ìõ±ß£¨ÕÛºÛ±ßPM³ýÍ⣩ÓëAC´¹Ö±£¿Èô´æÔÚ£¬ÇëÇó³öxµÄÖµ£»Èô²»´æÔÚ£¬Çë˵Ã÷ÀíÓÉ£®
ÒÑÖª£ºÈçͼ£¬ÔÚ¡÷ABCÖУ¬AB£½AC£½15£¬ cos¡ÏA£½£®µãMÔÚAB±ßÉÏ£¬AM£½2MB£¬µãPÊDZßACÉϵÄÒ»¸ö¶¯µã£¬ÉèPA£½x£®
£¨1£©Çóµ×±ßBCµÄ³¤£»
£¨2£©ÈôµãOÊÇBCµÄÖе㣬Áª½ÓMP¡¢MO¡¢OP£¬ÉèËıßÐÎAMOPµÄÃæ»ýÊÇy£¬Çóy¹ØÓÚxµÄº¯Êý¹Øϵʽ£¬²¢³öд³öxµÄÈ¡Öµ·¶Î§£»
£¨3£©°Ñ¡÷MPAÑØ×ÅÖ±ÏßMP·ÕÛºóµÃµ½¡÷MPN£¬ÊÇ·ñ¿ÉÄÜʹ¡÷MPNµÄÒ»Ìõ±ß£¨ÕÛºÛ±ßPM³ýÍ⣩ÓëAC´¹Ö±£¿Èô´æÔÚ£¬ÇëÇó³öxµÄÖµ£»Èô²»´æÔÚ£¬Çë˵Ã÷ÀíÓÉ£®
£¨1£©BC£½3
£¨2£©y £½x£«£® 0£¼x¡Ü15£©
£¨3£©x£½2»ò5»ò14ʱÂú×ã¡÷MPNµÄÒ»Ìõ±ßÓëAC´¹Ö±
£¨2£©y £½x£«£® 0£¼x¡Ü15£©
£¨3£©x£½2»ò5»ò14ʱÂú×ã¡÷MPNµÄÒ»Ìõ±ßÓëAC´¹Ö±
ÊÔÌâ·ÖÎö£º½â£º£¨1£©×÷BH¡ÍACÓÚµãH£¨Èçͼһ£©£¬
¡ßÔÚRt¡÷ABHÖУ¬cos¡ÏA£½£¬AB£½15£¬
¡àAH£½12¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡£¨1·Ö£©
¡àBH£½9£®¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡£¨1·Ö£©
¡ßAC£½15
¡àCH£½3£®¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡¡£¨1·Ö£©
¡ßBC2£½BH2£«CH2£¬¡àBC2£½92£«32£½90£¬¡àBC£½3£®¡£¨1·Ö£©
£¨2£©×÷OE¡ÍABÓÚµãE£¬OF¡ÍACÓÚµãF£¨Èçͼһ£©£¬
¡ßµãOÊÇBCµÄÖе㣬¡àOE£½OF£½BH£½£®
¡ßAM£½2MB£¬AB£½AC£½15£¬¡àAM£½10£¬BM£½5£®
¡ßPA£½x£¬¡àPC£½15£x£¬
¡ày £½ S¡÷ABC£S¡÷BOM£S¡÷COP£½BH¡¤AC¨DOE¡¤BM¨DOF¡¤PC
£½¡Á9¡Á15££¡¡¡¡¡¡¡£¨1+1·Ö£©
£½x£«£®¡¡¡¡¡¡¡¡¡¡¡¡¡£¨1·Ö£©
¶¨ÒåÓò£º£¨0£¼x¡Ü15£©£®¡¡¡¡¡¡¡¡¡¡¡ £¨1·Ö£©
£¨3£©¢Ùµ±PN¡ÍACʱ£¨Èçͼ¶þ£©£¬×÷MG¡ÍACÓÚµãG£¬
¡ßÔÚRt¡÷AMGÖУ¬cos¡ÏA£½£¬AM£½10
¡àAG£½8£¬¡àMG£½6£®
¢ÙÈôµãP1ÔÚAGÉÏ£¬ÓÉÕÛµþÖª£º¡ÏAP1M£½135¡ã£¬¡à¡ÏMP1G£½45¡ã£®
¡ßMG¡ÍAC£¬¡àP1G£½MG£½6£¬¡¡¡£¨1·Ö£©¡àAP1£½AG£P1G£½2£®¡¡¡¡£¨1·Ö£©
¢ÚÈôµãP2ÔÚCGÉÏ£¬ÓÉÕÛµþÖª£º¡ÏAP2M£½45¡ã£®
¡ßMG¡ÍAC£¬¡àP2G£½MG£½6£¬¡àAP2£½AG£«P2G£½14£®¡¡¡¡£¨2·Ö£©
¢Ûµ±MN¡ÍACʱ£¨ÈçͼÈý£©£¬
ÓÉÕÛµþÖª£º¡ÏAMP3£½¡ÏNMP3£¬P3N3£½AP3£½x£¬MN3£½MA£½10£¬
¡àP3G£½8£x£¬GN3£½4£®
¡ßP3N32£½P3G2£«GN32£¬¡àx2£½£¨8£x£©2£«42£¬¡àx£½5£®¡¡£¨2·Ö£©
×ÛÉÏËùÊö£¬x£½2»ò5»ò14ʱÂú×ã¡÷MPNµÄÒ»Ìõ±ßÓëAC´¹Ö±£®
µãÆÀ£º±¾ÌâµÄ¿¼²éÔÚÓÚ½¨Á¢Èý½Çº¯ÊýÄ£ÐÍ£¬Ö÷Òª¿¼²éº¯ÊýµÄÓ¦Ó᣽â¾ö´ËÀàÎÊÌâͨ³£Óм¸¸ö²½Ö裺£¨1£©ÔĶÁÀí½â£¬ÈÏÕæÉóÌ⣻£¨2£©Òý½øÊýѧ·ûºÅ£¬½¨Á¢ÊýѧģÐÍ£»£¨3£©ÀûÓÃÊýѧµÄ·½·¨£¬µÃµ½Êýѧ½á¹û£¬ÆäÖйؼüÊǽ¨Á¢ÊýѧģÐÍ£®
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿