Edit I thought amssymb provides \cupdot which does what you want... but it doesn't.
\usepackage{MnSymbol} provides \cupdot and \bigcupdot but is incompatible with amssymb which is unfortunate.
Sometimes disjoint union is depicted using \sqcup which has the advantage of being in amssymb
BYJUS
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Set Theory Symbols
If A ⊆ B, then the elements of A are also the elements of set B. ... The symbol for union of sets is denoted by ‘∪’. A ∪ B is equal to the sets that contains all the elements of set A and set B.
Published June 24, 2024 Views 31K
Wumbo
wumbo.net › symbols › union
Union Symbol (∪)
The set union symbol (∪) is used in math to represent the union operator in set theory.
What's this union symbol doing without anything on its left?
The "big union" symbol is used to denote a union of a large (or even infinite) number of elements. This notation tells us to successively apply the union operator to all elements which meet some criteria. Let's use a different example to illustrate what's going on. Suppose we wanted to know what's the union of all subsets of the positive integers with cardinality of at least 3? Well we could write: {1, 2, 3} ∪ {1, 2, 3, 4} ∪ {1, 2, 3, 4, 5} ∪ ... ∪ {17, 18, 19} ∪ ... But since there are infinitely many such subsets we can't possibly write them all. But what we could do is use the "big union" symbol with a subscript of: X ∈ ℤ+, |X| >= 3 More on reddit.com
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March 29, 2019[University] Set Theory - Union and Intersection
The union (big U) of some sets is one big set of all elements that are in at least one of the sets. The intersection (upside down U) is the set of all elements, that are in every one of the sets. More on reddit.com
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February 28, 2025How do you remember set theory basic symbols?
Subset symbol is like smaller/greater. Intersection is like logical and, union is like logical or. More on reddit.com
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January 14, 2024Why is the set intersection symbol an upside down "U" is it random or is there a reason
I don't know the history behind those choices, but note that those symbols correspond to the ∧ and ∨ symbols used for the AND and OR operations, respectively. If you have two sets, A and B, then A ⋂ B has the elements that are in both A AND B, and A ⋃ B has the elements that are in A OR B. More on reddit.com
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February 26, 2024What is the symbol for union of sets?
The symbol for union of sets is denoted by ‘∪’. A ∪ B is equal to the sets that contains all the elements of set A and set B.
byjus.com
byjus.com › maths › set-theory-symbols
Set Theory Symbols
What is union of sets with examples?
Consider two sets: A = {1, 2, 3} and B = {4, 5, 6}. The union of A and B is the collection of elements from both sets: A U B = { 1, 2, 3, 4, 5, 6}.
study.com
study.com › courses › business courses › gmat study guide and test prep
Union of Sets in Math | Definition, Symbol & Applications - Lesson ...
What does union mean in math sets?
The union of two or more sets is the collection of elements belonging to all of the sets. That is, if A and B are sets, then the union of A and B is the set of elements in A or in B.
study.com
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Union of Sets in Math | Definition, Symbol & Applications - Lesson ...
Videos
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Intersection of Sets, Union of Sets and Venn Diagrams - YouTube
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How to insert Union symbol in Word - YouTube
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What is a Union? (Set Theory) - YouTube
Universal set and absolute complement (video)
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Sets: Union and Intersection - YouTube
Intersection and union of sets (video)
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Edit I thought amssymb provides \cupdot which does what you want... but it doesn't.
\usepackage{MnSymbol} provides \cupdot and \bigcupdot but is incompatible with amssymb which is unfortunate.
Sometimes disjoint union is depicted using \sqcup which has the advantage of being in amssymb
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Another possibility to go around the problem that there is no such symbol in amssymb is to use the dot-accent: \dot{\bigcup} or also \dot\bigcup. This works for all symbols, and might very well be the reason that there are no dotted symbols in amssymb.
To let TeX treat such a new construct as an operator in terms of spacing though, you need to use \mathop and \mathbin, that's to say \mathop{\dot{\bigcup}} and \mathbin{\dot{\cup}}.
LaTeX-Tutorial.com
latex-tutorial.com › home › blog › union symbol in latex
Union symbol in LaTeX | LaTeX-Tutorial.com
November 20, 2021 - In mathematics, given two sets A and B, we define their union as the set formed by elements both from A and B. This new set is denoted by A ∪ B, and the symbol used for it can be produced with the command \cup inside math mode.
Study.com
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Union of Sets in Math | Definition, Symbol & Applications - Lesson | Study.com
November 9, 2015 - Here is an example showing this union symbol: Consider the example from the previous section concerning ice cream flavors. If the set of all people who bought vanilla is V and the set of all people who bought chocolate is C, then the set of those who bought both chocolate and vanilla (the union of the two sets) is {eq}V \cup C {/eq}.
GeeksforGeeks
geeksforgeeks.org › mathematics › set-theory-symbols
Set Symbols: List of Set Theory Symbols with Examples - GeeksforGeeks
In conclusion, the ∩ symbol is used to identify the elements that are shared by two or more sets. The intersection only produces sets that have elements that are shared by all sets that are being intersected.
Published 6 days ago
Encyclopedia Britannica
britannica.com › philosophy & religion › philosophical issues
Set theory - Operations, Elements, Relations | Britannica
1 week ago - Set theory - Operations, Elements, Relations: The symbol ∪ is employed to denote the union of two sets. Thus, the set A ∪ B—read “A union B” or “the union of A and B”—is defined as the set that consists of all elements belonging ...
Lumen Learning
courses.lumenlearning.com › mathforliberalartscorequisite › chapter › union-intersection-and-complement
Union, Intersection, and Complement | Mathematics for the Liberal Arts Corequisite
The intersection symbol looks a little like a big lower-case n, for in-tersect ... The union contains all the elements in either set: A ⋃ B = {red, green, blue, yellow, orange} Notice we only list red once.
Statistics LibreTexts
stats.libretexts.org › bookshelves › introductory statistics › support course for elementary statistics › sets
The Union and Intersection of Two Sets - Statistics LibreTexts
April 9, 2022 - An element is in the union of two sets if it is in the first set, the second set, or both. The symbol we use for the union is \(\cup\).
Math Is Fun
mathsisfun.com › sets › symbols.html
Set Symbols
A set is a collection of things, usually numbers. We can list each element (or "member") of a set inside curly brackets like this: Symbols save time and space when writing.
Expii
expii.com › t › union-of-sets-definition-examples-4303
Union of Sets - Definition & Examples - Expii
The union of sets includes every element from every set in the union. The union symbol ∪ means "or". The union looks for a number in one set or the other.
Piliapp
piliapp.com › symbols › union
∪ Union Symbol
The Union Symbol, symbolized by ∪, is used in set theory to denote the union of two or more sets.
Wikipedia
en.wikipedia.org › wiki › Union_(set_theory)
Union (set theory) - Wikipedia
4 weeks ago - In set theory, the union (denoted by ∪) of a collection of sets is the set of all elements in the collection. It is one of the fundamental operations through which sets can be combined and related to each other. A nullary union refers to a union of zero ( ... For explanation of the symbols used in this article, refer to the table of mathematical symbols.
OEISWiki
oeis.org › wiki › List_of_LaTeX_mathematical_symbols
List of LaTeX mathematical symbols - OeisWiki
This site is supported by donations to The OEIS Foundation · All the predefined mathematical symbols from the TeX package are listed below. More symbols are available from extra packages
CK-12 Foundation
ck12.org › all subjects › cbse math › venn diagrams and operations of sets › what does the union symbol (∪) mean in a venn diagram?
What does the union symbol (∪) mean in a Venn Diagram? - Examples, Symbol, & Definition | CK-12 Foundation
September 11, 2025 - If we have two sets @$\begin{align*}A\end{align*}@$ and @$\begin{align*}B,\end{align*}@$ the union of @$\begin{align*}A\end{align*}@$ and @$\begin{align*}B\end{align*}@$ is denoted by @$\begin{align*}A ∪ B\end{align*}@$ and it contains all the elements that are in @$\begin{align*}A,\end{align*}@$ ...
Probability Course
probabilitycourse.com › chapter1 › 1_2_2_set_operations.php
Set Operations | Union | Intersection | Complement | Difference | Mutually Exclusive | Partitions | De Morgan's Law | Distributive Law | Cartesian Product
or in $B$ (possibly both). For example, $\{1,2\}\cup\{2,3\}=\{1,2,3\}$. Thus, we can write $x\in(A\cup B)$ if and only if $(x\in A)$ or $(x\in B)$. Note that $A \cup B=B \cup A$. In Figure 1.4, the union of sets $A$ and $B$ is shown by the shaded area in the Venn diagram.
Reddit
reddit.com › r/askmath › what's this union symbol doing without anything on its left?
r/askmath on Reddit: What's this union symbol doing without anything on its left?
March 29, 2019 - The X at the end represent the sets being "unioned".
Cuemath
cuemath.com › algebra › union-of-sets
Union of Sets - Formula, Meaning, Examples | Finding a Union
The union of sets is analogous to arithmetic addition. The union of two given sets is the set that contains all the elements present in both sets. The symbol for the union of sets is "∪''. For any two sets A and B, the union, A ∪ B (read as A union B) lists all the elements of set A as ...
Quora
quora.com › What-is-the-U-and-upside-down-U-in-math
What is the U and upside down U in math? - Quora
To summarize: - U (∪) represents the union of two sets, combining all elements without duplication. - Upside-Down U (∩) represents the intersection of two sets, finding the common elements.
Math Vault
mathvault.ca › home › higher math resource hub › foundation of higher mathematics › mathematical symbols › set theory symbols
Comprehensive List of Set Theory Symbols | Math Vault
April 11, 2025 - A comprehensive collection of the most notable symbols in set theory, categorized by function into tables along with each symbol's meaning and example.