Èçͼ£¬Ä³Ö½Ïä³§ÓþØÐÎÓ²Ö½°å£¨PQST£©¸îÈ¥Ëĸö¾ØÐνǣ¬Éè¼ÆÎª°´ÐéÏßÕÛµþ³ÉµÄ³¤·½ÌåÖ½Ï䣮ÆäÖоØÐÎABCDΪ³¤·½ÌåµÄϵ×Ãæ£¬Á½È«µÈ¾ØÐÎEFNM¡¢HGNMÆ´³É³¤·½ÌåÖ½Ïä¸Ç£¬ÉèÖ½Ï䳤ABΪx£®

£¨¢ñ£©Èô³¤·½ÌåÖ½ÏäµÄ³¤¡¢¿í¡¢¸ß·Ö±ðΪ80cm¡¢50cm¡¢40cm¡¢ÔòÓ²Ö½°åPQSTµÄ³¤¡¢¿íӦΪ¶à´ó£¿

£¨¢ò£©ÈôÓ²Ö½°åPQSTµÄ³¤PT=240cm£¬¿íTS=150cm£¬°´´ËÉè¼Æ£¬µ±Ö½ÏäµÄ³¤ABΪºÎֵʱ£¬Ö½ÏäÌå»ý×î´ó£¿²¢¼ÆËã×î´óÌå»ý£®

 

£¨¢ñ£©ÓÉÌâÒ⣺PQ=AB+2H1A=80+2¡Á40=160£¨cm£©£¬

           PT=AD+2AH+2HM=2AD+2AH=2¡Á50+2¡Á40=180£¨cm£©£®      ¡­¡­¡­¡­¡­¡­¡­¡­¡­¡­4·Ö

£¨¢ò£©¡ßPT=240£¬PQ=150£¬ABΪx£¨0£¼x£¼150£©£¬

      ¡àAH=AH1=£¨TS£­AB£©=£¨150£­x£©£®

       ¡ßAD= M1H+EM£¬AH=DE£¬

¡àAD=£¨MM1£­2AH£©=£¨PT£­2AH£©=[240£­£¨150£­x£©]=45+x£¬     ¡­¡­¡­¡­¡­7·Ö

          ¡àÖ½ÏäÌå»ýV£¨x£©= x£¨150£­x£©£¨45+x£©=£­ x3+15 x2+3375x£®    ¡­¡­¡­¡­¡­¡­¡­8·Ö

             V¡ä(x)=£­ x2+30 x+3375£®

           ÁîV¡ä(x)=0£¬x2£­40x£­4500=0£¬½âµÃ£ºx1=90£¬x2=£­50£¨²»ºÏÌâÒ⣬ÉáÈ¥£©£®¡­¡­¡­10·Ö

        µ±x¡Ê£¨0£¬90£©Ê±£¬V¡ä(x)£¾0£¬V£¨x£©ÊÇÔöº¯Êý£»

µ±x¡Ê£¨90£¬150£©Ê±£¬V¡ä(x)£¼0£¬V£¨x£©ÊǼõº¯Êý£¬

¡àµ±x=90ʱ£¬V£¨x£©È¡µ½¼«´óÖµV£¨90£©=243000£®             ¡­¡­¡­¡­¡­¡­¡­12·Ö

¡ßV£¨x£©ÔÚ£¨0£¬150£©ÉÏÖ»ÓÐÒ»¸ö¼«Öµ£¬ËùÒÔËüÊÇ×î´óÖµ£®

¡àµ±Ö½ÏäµÄ³¤AB=90ʱ£¬Ö½ÏäÌå»ý×î´ó£¬×î´óÌå»ýΪ243000£¨cm3£©£®¡­¡­¡­¡­¡­¡­14·Ö

Á·Ï°²áϵÁдð°¸
Ïà¹ØÏ°Ìâ

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£º

Èçͼ£¬Ä³Ö½Ïä³§ÓþØÐÎÓ²Ö½°å£¨PQST£©¸îÈ¥Ëĸö¾ØÐνǣ¬Éè¼ÆÎª°´ÐéÏßÕÛµþ³ÉµÄ³¤·½ÌåÖ½Ï䣮ÆäÖоØÐÎABCDΪ³¤·½ÌåµÄϵ×Ãæ£¬Á½È«µÈ¾ØÐÎEFNM¡¢HGNMÆ´³É³¤·½ÌåÖ½Ïä¸Ç£¬ÉèÖ½Ï䳤ABΪx£®
£¨¢ñ£©Èô³¤·½ÌåÖ½ÏäµÄ³¤¡¢¿í¡¢¸ß·Ö±ðΪ80cm¡¢50cm¡¢40cm¡¢ÔòÓ²Ö½°åPQSTµÄ³¤¡¢¿íӦΪ¶à´ó£¿
£¨¢ò£©ÈôÓ²Ö½°åPQSTµÄ³¤PT=240cm£¬¿íTS=150cm£¬°´´ËÉè¼Æ£¬µ±Ö½ÏäµÄ³¤ABΪºÎֵʱ£¬Ö½ÏäÌå»ý×î´ó£¿²¢¼ÆËã×î´óÌå»ý£®
¾«Ó¢¼Ò½ÌÍø

²é¿´´ð°¸ºÍ½âÎö>>

¿ÆÄ¿£º¸ßÖÐÊýѧ À´Ô´£º ÌâÐÍ£º½â´ðÌâ

Èçͼ£¬Ä³Ö½Ïä³§ÓþØÐÎÓ²Ö½°å£¨PQST£©¸îÈ¥Ëĸö¾ØÐνǣ¬Éè¼ÆÎª°´ÐéÏßÕÛµþ³ÉµÄ³¤·½ÌåÖ½Ï䣮ÆäÖоØÐÎABCDΪ³¤·½ÌåµÄϵ×Ãæ£¬Á½È«µÈ¾ØÐÎEFNM¡¢HGNMÆ´³É³¤·½ÌåÖ½Ïä¸Ç£¬ÉèÖ½Ï䳤ABΪx£®
£¨¢ñ£©Èô³¤·½ÌåÖ½ÏäµÄ³¤¡¢¿í¡¢¸ß·Ö±ðΪ80cm¡¢50cm¡¢40cm¡¢ÔòÓ²Ö½°åPQSTµÄ³¤¡¢¿íӦΪ¶à´ó£¿
£¨¢ò£©ÈôÓ²Ö½°åPQSTµÄ³¤PT=240cm£¬¿íTS=150cm£¬°´´ËÉè¼Æ£¬µ±Ö½ÏäµÄ³¤ABΪºÎֵʱ£¬Ö½ÏäÌå»ý×î´ó£¿²¢¼ÆËã×î´óÌå»ý£®

²é¿´´ð°¸ºÍ½âÎö>>

ͬ²½Á·Ï°²á´ð°¸