求四阶行列式 1 3 0 2 2 2 1 3 0 2 1 3 0 0 3 -2

你可以直接用excel计算,D=42
演示一下吧：D=|1 3 0 2| = |1 3 0 2|
2 2 1 3 0 -4 1 -1 【r2-r1*2】
0 2 1 3 0 2 1 3
0 0 3 -2 0 0 3 -2
=|1 3 0 2| =|1 3 0 2|
0 0 3 5 [r2+r3*2] 0 0 3 5
0 2 1 3 0 2 1 3
0 0 3 -2 0 0 0 -7 [r4-r3]
=-|1 3 0 2| =(-1)*2*3*(-7)=42 [对角线连乘]
0 2 1 3 [r2、r3交换]
0 0 3 5
0 0 0 -7