说明：  计算逆矩阵，在矩阵后面夹带一个单位矩阵，然后把前面那一个矩阵处理成对角线单位矩阵，后面的那个矩阵就是逆矩阵。
(Computing inverse matrix, a unit entrainment in the matrix behind the matrix, and then in front of it is processed into a matrix, diagonal matrix, the latter matrix that is the inverse matrix.)