[問題] 問一題排列組合
甲.乙.丙.丁...共七人圍一圓桌而坐,若甲乙兩人必相鄰,甲丙兩人絕不相鄰
則有幾種方法?
我是今年才畢業的 新的課綱排列組合把環型排列刪掉了 所以沒學過@@
這是就讀高職的表妹問的
我的方法是甲乙綁一起 共五個先排 之後再丙差空隔
所以5!*4*2/5=192
但答案是720 差的有點多@@
她問老師後 老師也說不會...希望板上強者能教我一下!!!
補充一下選項 A.144 B.192 C.560 D.720
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※ 編輯: kawcoco04 來自: 140.116.109.199 (10/08 00:14)
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那這樣是192*2囉? 那我的算法哪裡出錯了? 我有*2了@@
※ 編輯: kawcoco04 來自: 140.116.109.199 (10/08 00:19)
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