## 编译环境 操作系统 * [ ] Windows 7/8/10 * [ ] macOS * [ ] Linux `若需勾选，请把[ ]改成[x]` Tex发行版 * [ ] TexLive `年份` * [ ] MikTeX `版本号` * [ ] CTeX `若需勾选，请把[ ]改成[x]` ## 我的问题 ``` \begin{align} &D_{\alpha \beta \gamma}=\left[\begin{array}{lll} D_{11} & D_{12} & D_{13} \\ D_{21} & D_{22} & D_{23} \\ D_{31} & D_{32} & D_{33} \end{array}\right] = \left[\begin{array}{l} \cos \beta \cos \gamma \\ \cos \beta \sin \gamma \\ -\sin \beta \end{array}\right.\\ &\mathrel{\phantom{=}} \left.\begin{array}{ll} -\cos \alpha \sin \gamma+\sin \alpha \sin \beta \cos \gamma & \sin \alpha \sin \gamma+\cos \alpha \sin \beta \cos \gamma \\ \cos \alpha \cos \gamma+\sin \alpha \sin \beta \sin \gamma & -\sin \alpha \cos \gamma+\cos \alpha \sin \beta \sin \gamma \\ \sin \alpha \cos \beta & \cos \alpha \cos \beta \end{array}\right] \end{align} ```