利用矩阵的初等变换可以方便地求矩阵的逆阵:11当可逆时,考虑如下式子:AAAEEA112lPPPAEEA121令,则有lAPPP12().即对矩阵施行初等行变换,当把变成时,原来的就变成nnAEAEEA1123221,.343设求AA解例1103620012520001321100343010122001321EA122rr13r3r111...