| 单词 | permutation |
| 释义 | Word Frequency permutation(ˌpɜːmjʊˈteɪʃən) noun 1. mathematics a. an ordered arrangement of the numbers, terms, etc, of a set into specified groups the permutations of a, b, and c, taken two at a time, are ab, ba, ac, ca, bc, cb b. a group formed in this way. The number of permutations of n objects taken r at a time is n!/(n–r)! Symbol: nPr. Compare combination (sense 6)2. a combination of items made by reordering 3. an alteration; transformation 4. a fixed combination for selections of results on football pools Usually shortened to: permDerived forms permutational (ˌpermuˈtational) adjective Word origin C14: from Latin permūtātiō, from permūtāre to change thoroughly; see mutation |
| 随便看 |
英语词典包含233703条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。