请输入您要查询的字词:

 

单词 permutations and combinations
释义 permutations and combinations
A combination is any subset of a particular set of objects, regardless of the order of selection. If the set consists of n objects, r objects can be selected giving n!/r!(n - r)! different combinations. This can be written nCr.
A permutation is an ordered subset (i.e. attention is paid to the order of selection or arrangement) of a particular set of objects. If the set consists of n objects, r such objects can be selected to give n!/(n - r)! permutations. This is written nPr
随便看

 

物理辞典收录了3346条物理词条,基本涵盖了常用物理知识及物理英语单词词组的翻译及用法,是物理学习的有利工具。

 

Copyright © 2000-2023 Newdu.com.com All Rights Reserved
更新时间:2025/6/23 12:34:10