SETS 1

OBJECTIVES 

1. Define Sets 

2. Understand types of sets

What is sets? 

A set is a collection of well defined entities. objects, or elements. 

Types of sets:

1. Universal Sets - it is a collection of all elements in a application. All the sets in that application are subset of this universal sets. 

Example : 

We may define U as the set of all Euro Qualifiers on european cup (football). In this case, set of all euro qualifiers is a subset of U, Set of all Asean qualifiers is subset of of U and America is also subset of U. 

2. null/ Empty Sets - it is an empty set contains no elements. it is symbolize as ∅. 

Example : 

{ } = ∅

A= {1,3,5,7}

B= {2,4,6,8}

A⋂ B= { } = ∅

3. Equal Sets - it is a two sets contain the same elements they are said to be equal. 

Example : 

If A = {2,3, 4} and B = {4,2,3}, they are equal as every element of set A is an element of set B. 

4. Equivalent Sets - it is a set if the cardinalities of two sets are same. 

Example : 

If A = {2,3,4} and B = {5,6,7}, they are equivalent as cardinality of A is equal to the cardinality of B. 

|A| = |B| = 3