是a 1 0 0
-1 b 1 0
0 -1 c 1
0 0 -1 d
上式=(r1+ar2)=
0 1+ab a 0
-1 b 1 0
0 -1 c 1
0 0 -1 d=【r1+(ab+1)r3】
0 0 c(ab+1)+a ab+1
-1 b 1 0
0 -1 c 1
0 0 -1 d=【r1+(abc+a+c)r4】
0 0 0 ab+1+d(abc+a+c)
-1 b 1 0
0 -1 c 1
0 0 -1 d=按(1,4)元展开
abcd+ad+cd+ab+1
是a 1 0 0
-1 b 1 0
0 -1 c 1
0 0 -1 d
上式=(r1+ar2)=
0 1+ab a 0
-1 b 1 0
0 -1 c 1
0 0 -1 d=【r1+(ab+1)r3】
0 0 c(ab+1)+a ab+1
-1 b 1 0
0 -1 c 1
0 0 -1 d=【r1+(abc+a+c)r4】
0 0 0 ab+1+d(abc+a+c)
-1 b 1 0
0 -1 c 1
0 0 -1 d=按(1,4)元展开
abcd+ad+cd+ab+1