線代 ⟩ 矩陣 ⟩ 矩陣公式表
所有矩陣相關公式會放在這裡,方便查閱。
(A+B)ij=Aij+Bij(\mathbf{A+B})_{ij} = \mathbf{A}_{ij} + \mathbf{B}_{ij}(A+B)ij=Aij+Bij
定義
(kA)ij=k(Aij)({\color{orange}k}\mathbf{A})_{ij} = {\color{orange}k}(\mathbf{A}_{ij})(kA)ij=k(Aij)
(Ai∗)T=(AT)∗i(\mathbf{A}_{{\color{red}{i}} *} )^{\color{orange}{T}} =(\mathbf{A}^{\color{orange}{T}} )_{*\color{red}{i}}(Ai∗)T=(AT)∗i
引理
(A∗j)T=(AT)j∗(\mathbf{A}_{* {\color{red}{j}} } )^{\color{orange}{T}} =(\mathbf{A}^{\color{orange}{T}} )_{{\color{red}{j}} *}(A∗j)T=(AT)j∗
(AB)T=BTAT\mathbf{(AB)}^T = \mathbf{B}^T \mathbf{A}^T(AB)T=BTAT
定理
(AB)ij=ai1b1j+ai2b2j+⋯+aipbpj(\mathbf{AB})_{{\color{blue}{i}}{\color{red}{j}}} = a_{i1}b_{1j} + a_{i2}b_{2j} + \cdots + a_{ip}b_{pj} (AB)ij=ai1b1j+ai2b2j+⋯+aipbpj
(AB)ij=Ai∗B∗j(\mathbf{AB})_{{\color{blue}{i}}{\color{red}{j}}} = \mathbf{A}_{{\color{blue}{i}}*} \mathbf{B}_{*\color{red}{j}}(AB)ij=Ai∗B∗j
(A∗kBk∗)ij=AikBkj( \mathbf{A}_{*\color{red}{k}} \mathbf{B}_{{\color{red}{k}}*} ) _{{\color{blue}{ij}}} = \mathbf{A}_{{\color{blue}{i}} \color{red}{k}} \mathbf{B}_{{\color{red}{k}} {\color{blue}{j}}} (A∗kBk∗)ij=AikBkj
表格疊加法 (引理)
AB=A∗1B1∗+A∗2B2∗+⋯+A∗pBp∗\mathbf{AB} = \mathbf{A}_{*\color{red}{1}} \mathbf{B}_{{\color{red}{1}}*} + \mathbf{A}_{*\color{red}{2}} \mathbf{B}_{{\color{red}{2}}*} + \cdots + \mathbf{A}_{*\color{red}{p}} \mathbf{B}_{{\color{red}{p}}*}AB=A∗1B1∗+A∗2B2∗+⋯+A∗pBp∗
表格疊加法 (定理)
類結合律:k(AB)=(kA)B=A(kB){\color{orange}k} (\mathbf{AB}) = ({\color{orange}k}\mathbf{A)B} = \mathbf{A} ({\color{orange}k}\mathbf{B})k(AB)=(kA)B=A(kB)
性質
結合律: (AB)C=A(BC)\mathbf{(AB)C} = \mathbf{A(BC)}(AB)C=A(BC)
Last updated 2 years ago
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