Sets and Set Operations

Set
A collection of distinct elements or objects.
Example: A = {1, 2, 3}
Empty Set (∅)
A set that contains no elements.
Example: ∅ = {}
Membership (∈)
Shows that an element belongs to a set.
Example: 2 ∈ {1, 2, 3}
Subset (⊆)
A set whose elements are all contained in another set.
Example: {1, 2} ⊆ {1, 2, 3}
Union (∪)
Combines all elements from two sets without duplicates.
Example: {1, 2} ∪ {2, 3} = {1, 2, 3}
Intersection (∩)
Contains only the elements common to both sets.
Example: {1, 2, 3} ∩ {2, 3, 4} = {2, 3}
Difference (\)
Contains elements in one set that are not in another set.
Example: {1, 2, 3} \ {2, 3} = {1}

Multiple Choice Quiz

1. What is a set?



2. What does ∪ mean?



3. What is the intersection of {1,2,3} and {2,3,4}?



4. What does ⊆ mean?



5. What is {1,2,3} \ {2,3}?