z = \frac{x}{y}

C_1 \quad= \quad c_2 + c_4^3

$$
y = \sqrt {x_1^2 + x_2^2 + x_3^2 + x_4^2}
$$

$$
y = \sqrt [3]{x_1^2 + x_2^2 + x_3^2 + x_4^2}
$$

$$\overrightarrow{AB} = \overrightarrow{b} + \overrightarrow{a}$$

$$ c = a \cdot c $$

$$
\lim_{x\rightarrow0} \sin(x+y)
$$
$$
\lim_{x\rightarrow0} \frac{\sin(x)}{x} = 1
$$

$$
\int_{0}^{\frac{\pi}{2}}
$$

$$
\sum_{i=1}^{n}
$$

$$
\prod_\epsilon
$$

$ a, b, c \neq \{ \{ a\}, b, c\} $
{ 和 } 是保留字需要‘\’转义

$ 1 + (\frac{1}{1-x^2})^3 $

$ 1 + \left(\frac{1}{1-x^2}\right)^3 $

$$ \left(\left(x+y\right)\left(x-y\right)\right)^2 $$

$$ \big((x+y)(x-y)\big)^2 $$

$ \big( \quad \big)$

$ \Big( \quad \Big)$

$ \bigg( \quad \bigg)$

$ \Bigg( \quad \Bigg)$

$$
 \left[
 \begin{matrix}
   1 & 2 & 3 \\\
   4 & 5 & 6 \\\
   7 & 8 & 9
  \end{matrix}
  \right]
$$

$$
\begin{bmatrix}
1&2&3\\\
4&5&6\\\
7&8&9
\end{bmatrix}
$$

$\cdots$

$\ddots$ 

$\vdots$ 

$$
\begin{bmatrix}
1&2&\cdots&4\\\
7&6&\cdots&5\\\
\vdots&\vdots&\ddots&\vdots\\\
8&9&\cdots&0
\end{bmatrix}
$$