Question

四阶行列式一共有几项组成?像三阶是六项.四阶呢?谢谢回答.

Answer 1

3 阶是 3! = 3*2*1 = 6 项

4 阶是 4! = 4*3*2*1 = 24 项

n 阶行列式有 n! = n(n-1)(n-2)...2*1 项