中五附加數學(請教)
回答 (2)
2009-10-30 1:51 am
2009-10-30 1:48 am
答案是 n - 1.
如 (5-1)!/(5-2)! = 4!/3!=4.
如 (5-1)!/(5-2)! = 4!/3!=4.
收錄日期: 2021-04-23 20:44:36
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20091029000051KK00973