Mathematics Q1 7

• Set


  A group or collection of objects
• Set


  • Named using capital letters
  • Each object in a set is called a member or an element
• Types of sets


  • Integers
  • Whole numbers
  • Counting numbers
  • Even numbers
  • Odd numbers
  • Prime numbers
  • Composite numbers
  • Perfect squares
  • Multiples
  • Factors
• Element


  An object that is part of a set
• Well-defined set


  A set where the membership criteria is clear and unambiguous
• Not well-defined set


  A set where the membership criteria is unclear or subjective
• Well-defined sets


  • Set of primary colors
  • Set of months in a year
  • Set of even numbers
• Not well-defined sets


  • Set of beautiful girls in school
  • Set of popular outdoor activities
  • Set of excellent singers
• Empty set/Null set


  A set with no members or elements
• Cardinality


  The number of elements in a set
• Cardinality is denoted by the symbol n(set)
• Cardinality calculations


  • n(set of primary colors) = 3
  • n(set of school days in a week) = 5
  • n(set of days in a week starting with A) = 0