陳鍾誠

Version 1.0

Tex數學式寫法

簡易算式

符號說明LaTex 寫法
$\simeq$approximately equal to (趨近)\simeq
$\equiv$equivlent to (全等、定義)\equiv
$\propto$proportional to (正比)\propto
$\infty$infinity (無限大)\infty
$x \mapsto a$x maps to ax \mapsto a
$x \to a$x approaches ax \to a
$\lim_{x \to a} f(x)$f(x) – 當 x 趨近於 a 時,\lim_{x \to a} f(x)
$\arg \max_x f(x)$最大化 f(x)\arg \max_x f(x)
$\arg \min_x f(x)$最小化 f(x)\arg \min_x f(x)
$\lceil x \rceil$ceil 函數 (天花板)\lceil x \rceil
$\lfloor x \rfloor$floor 函數 (地板)\lfloor x \rfloor
$\hat{\theta}$最大似然估計\hat{\theta}

空白的寫法

no space34no space34
, \thinspace3 4! \negthinspace34
: \medspace3 4\negmedspace34
; \thickspace3 4\negthickspace34
\quad3 4
\qquad3 4

常用符號

寫法顯示寫法顯示寫法顯示寫法顯示
\forall$\forall$\exists$\exists$\infty$\infty$\pm$\pm$
\div$\div$\times$\times$\cap$\cap$\cup$\cup$
\le$\le$\ge$\ge$\ll$\ll$\gg$\gg$
\neq$\neq$\nleq$\nleq$\ngeq$\ngeq$\not<$\not<$
\not>$\not>$\not=$\not=$\not\le$\not\le$\not\ge$\not\ge$
\equiv$\equiv$\supset$\supset$\subset$\subset$\supseteq$\supseteq$
\subseteq$\subseteq$\in$\in$\ni$\ni$\approx$\approx$
\vdash$\vdash$\rightarrow$\rightarrow$\leftarrow$\leftarrow$\Rightarrow$\Rightarrow$
\Leftarrow$\Leftarrow$\Leftrightarrow$\Leftrightarrow$

運算符號

寫法顯示
\sum_{i=0}^n f(x)$\sum_{i=0}^n f(x)$
\frac{a}{x^2}$\frac{a}{x^2}$
(\frac{a}{x} )^2$(\frac{a}{x} )^2$
\left(\frac{a}{x} \right)^2$ \left(\frac{a}{x} \right)^2$
\sum_{i=0}^n f(x)$\sum_{i=0}^n f(x)$
\sum_{i=0}^n f(x)$\sum_{i=0}^n f(x)$

大型括號 (Bracketing Symbols)

寫法顯示寫法顯示寫法顯示
{$\{$}$\}$\rangle$\rangle$
\backslash$\backslash$\lfloor$\lfloor$\rfloor$\rfloor$
\lceil$\lceil$\rceil$\rceil$\langle$\langle$
  • () 大型括號使用:\left( 與 \right),例如:\left(\frac{a}{x} \right)^2 會呈現 $\left(\frac{a}{x} \right)^2$

  • [] 大型括號使用:\left[ 與 \right],例如:\left[\frac{a}{x} \right]^2 會呈現 $\left[\frac{a}{x} \right]^2$

上標

寫法顯示寫法顯示寫法顯示寫法顯示
\hat{x}$\hat{x}$\dot{x}$\dot{x}$\bar{x}$\bar{x}$\vec{x}$\vec{x}$

數學大寫粗體

參考:LaTeX 教材:黑板粗體字 – http://libai.math.ncu.edu.tw/bcc16/7/latex/16.shtml

  • 範例:\Bbb{ Y = X \beta + E } 會顯示成 $\Bbb{ Y = X \beta + E }$

  • 範例:\mathbb{ Y = X \beta + E } 會顯示成 $\mathbb{ Y = X \beta + E }$

  • 範例:\mathcal{ Y = X \beta + E } 會顯示成 $\mathcal{ Y = X \beta + E }$

單行範例

f(n) = \sum^{N-1}_{k=0} F(k) e^{i 2 \pi k} \frac{n}{N}
f(n) = \sum^{N-1}_{k=0} F(k) e^{i 2 \pi k} \frac{n}{N}

單行範例

e = lim_{n \rightarrow \infty}\; 1+\frac{1}{1!}+\frac{1}{2!}+...+\frac{1}{n!}
e = lim_{n \rightarrow \infty}\; 1+\frac{1}{1!}+\frac{1}{2!}+...+\frac{1}{n!}

單行範例

e = lim_{n \rightarrow \infty} (1+\frac{1}{x})^x
e = lim_{n \rightarrow \infty} (1+\frac{1}{x})^x

複雜範例

 \begin{split}
    \mathbf{T n} &= \left[T_{ij} \mathbf{e}_i \otimes \mathbf{e}_j \right] n_k \mathbf{e}_k \\
                        & = T_{ij} n_k \left(\mathbf{e}_i \otimes \mathbf{e}_j\right) \mathbf{e}_k \\
                        & = T_{ij} n_j \mathbf{e}_i
 \end{split}
 \begin{split}
    \mathbf{T n} &= \left[T_{ij} \mathbf{e}_i \otimes \mathbf{e}_j \right] n_k \mathbf{e}_k \\
                        & = T_{ij} n_k \left(\mathbf{e}_i \otimes \mathbf{e}_j\right) \mathbf{e}_k \\
                        & = T_{ij} n_j \mathbf{e}_i
 \end{split}

多行陳述

\begin{align*}
& (1)\;  S \in F; \\
& (2)\;  if\; A \in F,\;then\; \bar{A} \in F;  \\
& (3)\;  if\; A \in F, B \in F,\;then\; A \cup B \in F;  \\
\end{align*}
\begin{align*}
& (1)\;  S \in F; \\
& (2)\;  if\; A \in F,\;then\; \bar{A} \in F;  \\
& (3)\;  if\; A \in F, B \in F,\;then\; A \cup B \in F;  \\
\end{align*}

多行範例

\begin{eqnarray} 
f'(x) & = & \frac{d f(x)}{dx} = c_1+c_2*2*x+c_3*3*x^2+c_4*4*x^3+... \\
f''(x) & = & \frac{d f'(x)}{dx}  = c_2*2*1+c_3*3*2*x+c_4*4*3*x^2+... \\
f'''(x) & = & \frac{d f''(x)}{dx} = c_3*3*2*1+c_4*4*3*2*x+... \\
... \\
f^k(x) & = & \frac{d f^{k-1}(x)}{dx} = c_k k!+c_{k+1} (k+1)! x+...
\end{eqnarray}
\begin{eqnarray} 
f'(x) & = & \frac{d f(x)}{dx} = c_1+c_2*2*x+c_3*3*x^2+c_4*4*x^3+... \\
f''(x) & = & \frac{d f'(x)}{dx}  = c_2*2*1+c_3*3*2*x+c_4*4*3*x^2+... \\
f'''(x) & = & \frac{d f''(x)}{dx} = c_3*3*2*1+c_4*4*3*2*x+... \\
... \\
f^k(x) & = & \frac{d f^{k-1}(x)}{dx} = c_k k!+c_{k+1} (k+1)! x+...
\end{eqnarray}

多行算式

多行等式 (eqnarray)

\begin{eqnarray} 
y &=& x^4 + 4      \nonumber \\
&=& (x^2+2)^2 -4x^2 \nonumber \\
&\le&(x^2+2)^2    \nonumber
\end{eqnarray}

顯示

\begin{eqnarray} 
y &=& x^4 + 4      \nonumber \\
&=& (x^2+2)^2 -4x^2 \nonumber \\
&\le&(x^2+2)^2    \nonumber
\end{eqnarray}

矩陣範例

\left[
  \begin{array}{ccc}
    T_{11} & T_{12} & T_{13} \\
    T_{21} & T_{22} & T_{23} \\
    T_{31} & T_{32} & T_{33} 
  \end{array}
\right]
\left[
  \begin{array}{ccc}
    T_{11} & T_{12} & T_{13} \\
    T_{21} & T_{22} & T_{23} \\
    T_{31} & T_{32} & T_{33} 
  \end{array}
\right]

矩陣範例

 \left\{
 \begin{array}{c}
    t_1 \\ t_2 \\ t_3
 \end{array}
 \right\} =
 \left[ 
 \begin{array}{ccc}
    T_{11} & T_{12} & T_{13} \\
    T_{21} & T_{22} & T_{23} \\
    T_{31} & T_{32} & T_{33} 
 \end{array} 
 \right]
 \left\{
 \begin{array}{c}
    n_1 \\ n_2 \\ n_3
 \end{array}
 \right\}
\left\{
 \begin{array}{c}
    t_1 \\ t_2 \\ t_3
 \end{array}
 \right\} =
 \left[ 
 \begin{array}{ccc}
    T_{11} & T_{12} & T_{13} \\
    T_{21} & T_{22} & T_{23} \\
    T_{31} & T_{32} & T_{33} 
 \end{array} 
 \right]
 \left\{
 \begin{array}{c}
    n_1 \\ n_2 \\ n_3
 \end{array}
 \right\}

範例

\int_1^x \frac{1}{x} dx = 1

範例

\frac{d}{dx} e^x = e^x

範例

e^x = 1+\frac{1}{1!} x + \frac{2}{2!} x^2 + ... \frac{n}{n!} x^n+ ...

範例

e^{i x} = cos(x) + i*sin(x)

範例

f(x) = c_0 + c_1 x + c_2 x^2 + ...+ c_k x^k+...=\sum_{k=0}^\infty c_k x^k

範例

c_k = \frac{f^k(0)}{k!}

範例

f(x) = f(0) + \frac{f'(0)}{1!} x +...+ \frac{f^k (0)}{k!} x^k+...=\sum^{\infty}_{k=0} 

\frac{f^k(0)}{k!} x^k

範例

f(x) = f(a) + \frac{f'(a)}{1!} x +...+ \frac{f^{k(a)}}{k!} x^k+...= \sum^\infty_{k=0} 

\frac{f^k(a)}{k!} x^k

範例

e^{i x} = 1 + i \frac{x}{1!} - \frac{x^2}{2!} - i \frac{x^3}{3!} + ... 

範例

cos(x) = 1 - \frac{x^2}{2!} + \frac{x^4}{4!} + ... 

範例

sin(x) = \frac{x}{1!} - \frac{x^3}{3!} + \frac{x^5}{5!} + ...

範例

e^{i x} = cos(x) + i * sin(x) 

範例

f(x) = \frac{a_0}{2} + \sum^{\infty}_{n=- \infty} a_n cos(n x)+ b_n sin(n x)

範例

cos(n x) + i * sin(n x) = e^{i n x}

範例

f(x) = \sum^{\infty}_{n=-\infty} F_n e^{i n x}

範例

F_t = \frac{1}{2\pi} \int^{\pi}_{-\pi} f(x) e^{i t x} dx

範例

x0xnx-n
$F_0 = \frac{1}{2}$$F_n= \frac{1}{2} (a_n- i b_n)$$F_{- n}= \frac{1}{2} (a_n+i b_n)$
$a_0 = 2 c_0$$a_n=F_n+F_{- n}$$ b_n=i (F_n-F_{-n})$

範例

f(t) = \int^\infty_{- \infty} F(x) e^{i 2 \pi x t} dt

範例

\begin{eqnarray}
f(x) = \left\{
 \begin{array}{c}
   1 \qquad x \in Z \\
   0 \qquad x \notin Z
 \end{array}
\right.
\end{eqnarray}
\begin{eqnarray}
f(x) = \left\{
 \begin{array}{c}
   1 \qquad x \in Z \\
   0 \qquad x \notin Z
 \end{array}
\right.
\end{eqnarray}

參考文獻