latex常用手册

latex

Posted by farmer3-c on September 6, 2025
  • $\sqrt[n]{x}$

    \sqrt[n]{x}

  • $x_i^2, a_{ij}^{kl}, \Gamma_{n}^{k},\sum_{i=1}^{n} x_i,\int_{a}^{b} f(x) \, dx,\lim_{x \to 0} f(x),\textit{f}_a^b$
    x_i^2, a_{ij}^{kl}, \Gamma_{n}^{k},\sum_{i=1}^{n} x_i,\int_{a}^{b} f(x) \, dx,\lim_{x \to 0} f(x),\textit{f}_a^b

  • $\frac{x}{y} $
    \frac{x}{y}

  • $ \begin{matrix} a & b & c \newline d & e & f \newline g & h & i \end{matrix} $
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          * 环境名-	语法示例-	效果
          * matrix	\begin{matrix} ... \end{matrix}	abcdabcd (无括号)
          * pmatrix	\begin{pmatrix} ... \end{pmatrix}	(abcd)(abcd) (圆括号)
          * bmatrix	\begin{bmatrix} ... \end{bmatrix}	[abcd][abcd] (方括号)
          * Bmatrix	\begin{Bmatrix} ... \end{Bmatrix}	{abcd}{abcd} (花括号)
          * vmatrix	\begin{vmatrix} ... \end{vmatrix}	∣∣∣abcd∣∣∣	abcd	(行列式竖线)
          * Vmatrix	\begin{Vmatrix} ... \end{Vmatrix}	∥∥∥abcd∥∥∥‖abcd‖ (双竖线,范数)
    
            
          \begin{matrix}
          a & b & c \\
          d & e & f \\
          g & h & i
          \end{matrix}    
    
  • $\frac{\partial f}{\partial x},\frac{\partial^2 f}{\partial x \partial y},\frac{\partial (f,g)}{\partial (x,y)} = \begin{vmatrix} \frac{\partial f}{\partial x} & \frac{\partial f}{\partial y} \newline \frac{\partial g}{\partial x} & \frac{\partial g}{\partial y} \end{vmatrix}$

    \frac{\partial f}{\partial x},\frac{\partial^2 f}{\partial x \partial y},\frac{\partial (f,g)}{\partial (x,y)} = \begin{vmatrix} \frac{\partial f}{\partial x} & \frac{\partial f}{\partial y} \\ \frac{\partial g}{\partial x} & \frac{\partial g}{\partial y} \end{vmatrix}

  • $\nabla$
    \nabla

  • $\alpha$
    \alpha
  • $\iff$
    \iff

  • $\implies$
    \implies

  • $\Delta$
    \Delta

  • $\mathrm{i}$
    \mathrm{i}

  • $\approx$
    \approx

  • $a \leq b ,a \geq b,a\neq b,a \ll b,a \gg b$ a \leq b,a \geq b,a\neq b,a \ll b,a \gg b

  • $\mathbf{A + B = C}$ $\mathbf{A + B = C}$

  • 集合表示:$A = { x \mid x > 0 }$ 集合表示:$A = \{ x \mid x > 0 \}$

  • $a \in A$ $a \in A$
  • $b \notin A$ $b \notin A$
  • $A \subset B$ $A \subset B$
  • $A \subsetneq B$ $A \subsetneq B$
  • $B \supset A$ $B \supset A$
  • $\mathbb{R}$
    $\mathbb{R}$
  • $p \land q$ $p \land q$
  • $p \lor q$ $p \lor q$
  • \[f(x) = \left\{ \begin{aligned} & x^2 & \text{if } x > 0 \newline & 0 & \text{if } x = 0 \newline & -x^2 & \text{if } x < 0 \newline \end{aligned} \right.\]
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      $$
      f(x) = 
      \left\{
      \begin{aligned}
      & x^2      & \text{if } x > 0 \newline
      & 0        & \text{if } x = 0 \newline
      & -x^2     & \text{if } x < 0 \newline
      \end{aligned}
      \right.
      $$
    
  • $\overline{A}$ $\overline{A}$

  • $A \xrightarrow[\text{下方条件}]{\text{上方条件}} B$ A \xrightarrow[\text{下方条件}]{\text{上方条件}} B

  • $\mathbf{a} \times \mathbf{b}$ \mathbf{a} \times \mathbf{b}

  • \[\min_{\substack{x_1, x_2 }} \left( x_1 + x_2 + P(x_1^2 + x_2^2 - 1) \right)\]
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$$
\min_{\substack{x_1, x_2 }} \left( x_1 + x_2 + P(x_1^2 + x_2^2 - 1) \right)
$$
  • $\Downarrow$ \Downarrow

  • $\underset{x_1, x_2}{\text{Min.}} \, x_1 + x_2 + \underset{\lambda \geq 0}{\text{Max.}} \, \lambda(x_1^2 + x_2^2 - 1)$ \underset{x_1, x_2}{\text{Min.}} \, x_1 + x_2 + \underset{\lambda \geq 0}{\text{Max.}} \, \lambda(x_1^2 + x_2^2 - 1)

  • 设矩阵 $A \in \mathbb{R}^{n \times n}$ 为对称矩阵:
    • 若 $A \succ 0$,则 $A$ 是严格正定矩阵
    • 若 $A \succeq 0$,则 $A$ 是半正定矩阵
    • 若 $A \prec 0$,则 $A$ 是严格负定矩阵
    • 若 $A \preceq 0$,则 $A$ 是半负定矩阵
  • $\forall$ \forall
  • $\exists$ \exists

  • $\infty$ \infty

  • $ \frac{\partial L(x,\lambda^,\mu^)}{\partial x}\bigg|{x=x^*} = \nabla f(x^*) + \sum{i=1}^{m} \lambda_i^* \nabla g_i(x^) + \sum_{j=1}^{p} \mu_j^ \nabla h_j(x^*) = 0 $
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    $
    \frac{\partial L(x,\lambda^*,\mu^*)}{\partial x}\bigg|_{x=x^*} = \nabla f(x^*) + \sum_{i=1}^{m} \lambda_i^* \nabla g_i(x^*) + \sum_{j=1}^{p} \mu_j^* \nabla h_j(x^*) = 0
    $
    
  • $\gamma$ \gamma
  • $\eta$ \eta
  • $\xi$ \xi
  • $\phi$ \phi
  • $\psi$ \psi
  • $\omega$ \omega
  • $\theta$ \theta
  • $\lambda$ \lambda
  • $\lfloor x \rfloor$ \lfloor x \rfloor
  • $\lceil x \rceil$ \lceil x \rceil