A substance is through the primary transformation into an uppertriangularmatrix, the transformation matrix is a unit lower triangular matrix.
实质上是将A通过初等行变换变成一个上三角矩阵，其变换矩阵就是一个单位下三角矩阵。
2
The authors characterize the forms of additive invertable operators preserving inverse matrix of the uppertriangularmatrix space over a field which characteristic is not 2 or 3 .
刻划了特征不为2及3的域上的上三角矩阵空间保逆矩阵的可逆加法算子的形式。
3
This article gives a Formula for finding inverse matrices of upper (down) triangularmatrix.