SETS AND VENN DIAGRAMS

and A = {Tuesday, Thursday}. These can be shown on a Venn diagram. The language of sets The universal set ( ) contains all the elements being considered in a particular problem. Monday Tuesday Wednesday Thursday Friday Saturday Sunday A Let = {days in the week} and A = {Tuesday, Thursday}. These can be shown on a Venn diagram. The set A has been shaded on the diagram. The number of elements in set A is denoted by n(A). n(A) = 2 The symbol means ‘is a member of’. The symbol means ‘is not a member of’.

Venn diagrams

The complement of set A is the set of all elements not in A.

The intersection of sets A and B is the set of elements that are in both A and B.

The union of sets A and B is the set of elements that are in A or B or both.

When the expressions are more complicated you may need to use some diagrams for your working out before deciding on your answer .

Example 1 A B A B A B

Example 2 A B A B A B

Example 3 A B A B

Example 4 A B A B A B

Example 5 A B A B A B

Example 6 A B C

Example 7 A B C

Example 8 A B C A B C A B C

Example 9 A B C A B C A B C

Example 10 A B C A B C A B C