luixiao1220的博客

UTF8gbsnTraceTr⁡(A)=∑iAii\operatorname{Tr}(\mathbf{A})=\sum_{i} A_{i i}Tr(A)=∑i​Aii​这是迹的定义,这里无需证明.Tr⁡(A)=∑iλi,λi=eig⁡(A)\operatorname{Tr}(\mathbf{A})=\sum_{i} \lambda_{i}, \quad \lambda_{i}=\o...

UTF8gbsn(AB)−1=B−1A−1(\mathbf{A B})^{-1}=\mathbf{B}^{-1} \mathbf{A}^{-1}(AB)−1=B−1A−1ABB−1A−1=A(BB−1=I)A−1=AA−1=IABB^{-1}A^{-1}=A(BB^{-1}=I)A^{-1}=AA^{-1}=IABB−1A−1=A(BB−1=I)A−1=AA−1=I,B−1A−1B^{-1...