一道英文数学题,是有关排序组合的
问题描述：
一道英文数学题,是有关排序组合的
Exactly 4 actors try out for 4 parts in a play.If each actor can perform any one part and no one will perform more than one part,how many different assignments of actors are possibe?
答
四对四的排列.
4*3*2*1=24.
即可能有二十四中排列方法.
你用排列数算也是这个结果的..这里不好打上下标..所以我就写了个式子...