1.矩阵的乘法
矩阵实现满足:内标相等
矩阵相乘之后的结果:前行后列
需要注意:1.矩阵的乘法不具有交换律:AB!=BA
2.矩阵的乘法满足分配律:A(B+C) = AB + AC
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方法1.凑定义法、
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方法2.长除法
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数字型矩阵求逆
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方法:利用行变换求A的逆:(A/E) —多次变换—>(E/A的逆)
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对于二阶矩阵求逆的秒杀法:两调一除
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1.若AX = B ——>则X = A的逆B
2.若XA = B ——>则X = BA的逆
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伴随矩阵的相关性质
A*称为A的伴随矩阵,且AA* = A*A = |A|E,A* = |A|A的逆
方阵的行列式的性质
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