1234 0421 例3D 0056 0008 1.234 04.21 D =a12a34=1.4·58=160 005.6 0008 上页例3 ? 0 0 0 8 0 0 5 6 0 4 2 1 1 2 3 4 D = = 11 22 33 44 0 0 0 8 0 0 5 6 0 4 2 1 1 2 3 4 D = = a a a a = 1 4  5  8 = 160