xixj/x”2
x”=（x1,x2...xn）不等于0|x|^2=x1^2+x2^2+...+xn^2
D=
1-x1^2/|x|^2-x1x2/|x|^2 ... -x1xn/|x|^2
-x2x1/|x|^2 1-x2^2/|x|^2 ... -x2xn/|x|^2
....
-xnx1/|x|^2-xnx2/|x|^2 ... 1-xn^2/|x|^2
加边
1 x1/|x|^2 x2/|x|^2 ...xn/|x|^2
0 1-x1^2/|x|^2-x1x2/|x|^2 ... -x1xn/|x|^2
0-x2x1/|x|^2 1-x2^2/|x|^2 ... -x2xn/|x|^2
....
0-xnx1/|x|^2-xnx2/|x|^2 ... 1-xn^2/|x|^2

ri + xi-1r1, i=2,3,...,n+1
1 x1/|x|^2 x2/|x|^2 ... xn/|x|^2
x110 ... 0
x201 ... 0
...
xn00 ... 1

c1-x1c2-x2c3-...-xncn+1
1-x1^2/|x|^2-...-xn^2/|x|^2x1/|x|^2 x2/|x|^2 ... xn/|x|^2
010 ... 0
001 ... 0
...
000 ... 1
=
0x1/|x|^2 x2/|x|^2 ... xn/|x|^2
010 ... 0
001 ... 0
...
000 ... 1

= 0