数学符号表: 一组常在数学表达式中出现的符号

${\displaystyle \neg (\neg A)\Leftrightarrow A}$ 

${\displaystyle x\neq y\Leftrightarrow \neg (x=y)}$ 

${\displaystyle a\in S}$ 

${\displaystyle a}$ 

${\displaystyle S}$ 

${\displaystyle a\not \in S}$ 表示${\displaystyle a}$ 不屬於${\displaystyle S}$ 

${\displaystyle A\subseteq B}$ 

${\displaystyle A}$ 

${\displaystyle B}$ 

${\displaystyle A\subset B}$ 

${\displaystyle A\subseteq B}$ 

${\displaystyle A\neq B}$ 

（有的地方记作${\displaystyle A\subsetneqq B}$ ）

${\displaystyle A\cap B\subseteq A}$ 

${\displaystyle \mathbb {Q} \subset \mathbb {R} }$ 

${\displaystyle \mathbb {Q} \subsetneqq \mathbb {R} }$ 

${\displaystyle A\supseteq B}$ 

${\displaystyle B}$ 

${\displaystyle A}$ 

${\displaystyle A\supset B}$ 

${\displaystyle A\supseteq B}$ 

${\displaystyle A\neq B}$ 

（有的地方记作${\displaystyle A\supsetneqq B}$ ）

${\displaystyle A\cup B\supseteq B}$ 

${\displaystyle \mathbb {R} \supset \mathbb {Q} }$ 

${\displaystyle \mathbb {R} \supsetneqq \mathbb {Q} }$ 

${\displaystyle A\setminus B}$ 

${\displaystyle A}$ 

${\displaystyle B}$ 

（有的地方记作${\displaystyle \complement _{A}B}$ ）

${\displaystyle \left\{1,2,3,4\right\}\setminus \left\{3,4,5,6\right\}=\left\{1,2\right\}}$ 

${\displaystyle \complement _{U}A=\left\{x|x\in U\ {\textrm {and}}\ x\notin A\right\}}$ 

${\displaystyle \left({\frac {8}{4}}\right)\div 2={\frac {2}{2}}=1}$ 

${\displaystyle 8\div \left({\frac {4}{2}}\right)={\frac {8}{2}}=4}$