A RetroSearch Logo

Home - News ( United States | United Kingdom | Italy | Germany ) - Football scores

Search Query:

Showing content from https://www.mathsisfun.com/sets/symbols.html below:

Set Symbols

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:

Common Symbols Used in Set Theory

Symbols save time and space when writing. Here are the most common set symbols

In the examples C = {1, 2, 3, 4} and D = {3, 4, 5}

Symbol Meaning Example { } Set: a collection of elements {1, 2, 3, 4} A ∪ B Union: in A or B (or both) C ∪ D = {1, 2, 3, 4, 5} A ∩ B Intersection: in both A and B C ∩ D = {3, 4} A ⊆ B Subset: every element of A is in B. {3, 4, 5} ⊆ D A ⊂ B Proper Subset: every element of A is in B,
but B has more elements. {3, 5} ⊂ D A ⊄ B Not a Subset: A is not a subset of B {1, 6} ⊄ C A ⊇ B Superset: A has same elements as B, or more {1, 2, 3} ⊇ {1, 2, 3} A ⊃ B Proper Superset: A has B's elements and more {1, 2, 3, 4} ⊃ {1, 2, 3} A ⊅ B Not a Superset: A is not a superset of B {1, 2, 6} ⊅ {1, 9} Ac Complement: elements not in A Dc = {1, 2, 6, 7}
When = {1, 2, 3, 4, 5, 6, 7} A − B Difference: in A but not in B {1, 2, 3, 4} − {3, 4} = {1, 2}


a ∈ A Element of: a is in A 3 ∈ {1, 2, 3, 4} b ∉ A Not element of: b is not in A 6 ∉ {1, 2, 3, 4} Ø Empty set = {} {1, 2} ∩ {3, 4} = Ø Universal Set: set of all possible values
(in the area of interest)  


P(A) Power Set: all subsets of A P({1, 2}) = { {}, {1}, {2}, {1, 2} } A = B Equality: both sets have the same members {3, 4, 5} = {5, 3, 4} A×B Cartesian Product
(set of ordered pairs from A and B) {1, 2} × {3, 4}
= {(1, 3), (1, 4), (2, 3), (2, 4)} |A| Cardinality: the number of elements of set A |{3, 4}| = 2 | Such that { n | n > 0 } = {1, 2, 3,...} : Such that { n : n > 0 } = {1, 2, 3,...} ∀ For All ∀x>1, x2>x
For all x greater than 1
x-squared is greater than x
∃ There Exists ∃ x | x2>x
There exists x such that
x-squared is greater than x
∴ Therefore a=b ∴ b=a


Natural Numbers {1, 2, 3,...} or {0, 1, 2, 3,...} Integers {..., −3, −2, −1, 0, 1, 2, 3, ...} Rational Numbers   Algebraic Numbers   Real Numbers   Imaginary Numbers 3i Complex Numbers 2 + 5i

RetroSearch is an open source project built by @garambo | Open a GitHub Issue

Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo

HTML: 3.2 | Encoding: UTF-8 | Version: 0.7.4