(2)设A= 为数那末 a4, 41r MA 4 s1 MA 例元=2,A=321 1×22×23×2 2A=3×22×21×2|=642 4×25×26×2)(81012(2)设 , 为数,那末 1 1 1 1            = s sr r A A A A A     . 1 1 1 1           = s sr r A A A A A          例 .           = 4 5 6 3 2 1 1 2 3  = 2, A 2 2 2 2 2 2 2 2 2                    = 4 5 6 3 2 1 1 2 3 2A . 8 10 12 6 4 2 4 4 6           =