Set Theory Symbols Flashcards
{ }
Set
a collection of elements
A ∪ B
Union
in A or B (or both)
A ∩ B
Intersection
in both A and B
A ⊆ B
Subset
A has some (or all) elements of B
A ⊂ B
Proper Subset
A has some elements of B
A ⊄ B
Not a Subset
A is not a subset of B
A ⊇ B
Superset
A has same elements as B, or more
A ⊃ B
Proper Superset
A has B’s elements and more
A ⊅ B
Not a Superset
A is not a superset of B
A∆B
Symmetric Difference
Objects that belong to A or B but not to their intersection
A⊖B
Symmetric Difference
Objects that belong to A or B but not to their intersection
A×B
Cartesian Product
Set of all ordered pairs from A and B
A×B = {(a,b)|a∈A , b∈B}
|A|
Cardinality
The number of elements of set A
A={3,9,14}, |A|=3
Ø
Empty Set
Ø = {} A = Ø
ℝ
Real Numbers
Can be defined as the union of both rational and irrational numbers.
ℂ
Complex Numbers
ℤ
Integer Numbers
Denote the set of integers.
ℤ={…,−3,−2,−1,0,1,2,3,…}
