Logic

Logic Symbol English Meaning Example
$\wedge$ Conjunction p $\wedge$ q
p and q.
$\vee$ Inclusive Disjunction p $\vee$ q
p or q.
$\neg$ Not $\neg$p
not p.
$\oplus$ Exclusive Or (xor) p $\oplus$ q
p exclusive or q.
$\implies$ Implies p $\implies$ q
p implies q.
$\iff$ Bi–conditional / if and only if (iff) p $\iff$ q
p iff q.

Number Sets

Number Set Symbol English Meaning Example
$\mathbb{N}$ Natural Numbers {1, 2, 3, 4,…}
$\mathbb{Z}$ Integers {-2, -1, 0, 1, 2…}
$\mathbb{Z}^+$ Positive Integers {1, 2, 3, 4…}
$\mathbb{Q}$ Rational Numbers {1/2, 1/4, 7/123…}
$\mathbb{R}$ Real Numbers {2.5, $\pi$, 3.3333, …}
$\mathbb{C}$ Complex Numbers $2 + 3 i$

Quantifiers

Qualifier Symbol English Meaning Example
$\isin$ Belongs To
Is In $n\in\mathbb{N}$
n is in the natural numbers.
$\forall$ For All $\forall n\in\Z$
For all n in the integers.
$\exists$ There Exists
For Some $\exists \;n \text{ such that }m > n$
There Exists an n such that m is greater than m.

Sets

Symbol English Meaning Example
$ S $
\newline
S = 3$
The cardinality of Set $S$ is 3.
$\isin$ Is In/Belongs To $n \isin \mathbb{N}$
$n$ is in the natural numbers.
$\notin$ Is Not In/Does Not Belong To $n \notin \mathbb{Z}$
$n$ is not in the integers.
$\emptyset$ or {} Empty Set Self-Explanatory.
$\subseteq$ Subset $A$ $\subseteq$ $B$
A is a subset of B.
$\subset$ Proper Subset $C$ $\subset$ $D$
C is a proper subset of D.
$P(S)$
S being some set Power Set $P(A)$
Power Set of A.
$\cup$ Union $A$ $\cup$ $B$
A union B.
$\cap$ Intersection $C$ $\cap$ $D$
C intersection D.
$-$ Difference $A$ $-$ ****$B$
A difference B.
$\times$ Cross Product $C$ $\times$ $D$
C cross D.

Set Builder Notation

<aside> 💡 In set builder notation, elements are defined as variables (which may be written in a certain form). Then, the variable is followed by a | (which means “such that”) and a rule.

</aside>

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