若<img src、"http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/3-2/image026.png" alt="" align="middle">均为零矩阵，则有<img src="http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/3-2/image040.png" alt="" align="middle">
若<img src、"http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/3-2/image034.png" alt="" align="middle">，<img src="http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/3-2/image035.png" alt="" align="middle">，则<img src="http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/3-2/image036.png" alt="" align="middle">
若<img src、"http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/3-2/image037.png" alt="" align="middle">，且<img src="http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/3-2/image038.png" alt="" align="middle">，则<img src="http://oss.ouchn.cn/ddzx/N601/gongxue/jjsx/img/3-2/image039.png" alt="" align="middle">
、数量矩阵是对称矩阵