Conventions in Set o Sets are usually denoted by capital letters A, B, C, X, Y, Z, etc. o The elements of a set are represented by small letters a, b, c, d etc. o
o
If a is an element of a set A, we say that“ a belongs to A” the Greek symbol ∈( epsilon) is used to denote the phrase‘ belongs to’. Thus, we write a ∈
If‘ b’ is not an element of a set A, we write b ∉ A and read“ b does not belong to A”.
o Objects, elements and members of a set are synonymous terms.
Examples: If V is set of vowels, a & b are alphabets, then a ∈ V but b ∉ V. P is set of prime factors of 30, then 3 ∈ P but 15 ∉ P.
There are two Methods of representing Set o Roster or tabular form. o Set-builder form.
Roster or Tabular Form In roster form, all the elements of a set are listed, the elements are being separated by commas and are enclosed within braces { }
E. g. the set of all number in a dice is described in roster form as { 1,2,3,4,5,6 }.
Points to be noted in roster form:
o In roster form, the order in which the elements are listed is immaterial. g. The set of all vowels in the English alphabet can be written as { a, e, i, o, u } or { a, u, i, o, e } or { u, e, i, o, a } or { o, e, i, a, u }