Memory tip : ONE ( Open No endpoint ). Open windows = Light Closed Window = Dark () Looks like O , so it is used for Open interval [] looks like closed box , so it is used for closed interval
Venn Diagrams
Most of the relationships between sets can be represented by means of diagrams known as Venn diagrams . Venn diagrams are named after the , John Venn . These diagrams consist of rectangles and closed curves usually circles . The universal set is represented usually by a rectangle and its subsets by circles .
In the Venn diagram below : U = { 1,2,3 , ..., 10 } is the universal set of which A = { 2,4,6,8,10 } is a subset .
Operation on Sets 1 . Union of sets 2 . Intersection of sets 3 . Difference of sets 4 . Complement of a Set