This document provides examples and definitions related to sets in mathematics. It begins by giving examples of sets, such as collections of flowers, books, students, and colors. It defines a set as a collection of well-defined objects. The document then discusses different ways to represent sets, such as using a descriptive statement, roster, or set-builder form. It provides examples of representing the set of even numbers less than 10 in these different forms. The document concludes by defining the elements of a set as the objects used to form the set and examples of denoting whether an element is or is not part of a given set.

1. MATHS COMMON CLASS
VIII Std
26/06/2018

2. Group formation
House wise
Section wise
All numbers which are natural
Set of mathematics books in library

3. Sets { }

4. Definition :
The collection of well-defined
Objects is known as a set.

5. Sets
•Example
•Non - example

6. Example : 1
A collection of “Yellow flowers”

7. Example : 2
A collection of ‘lovely flowers’

8. Example : 3
Interesting books in the library

9. Example : 4
All problems of this book, which are difficult to solve.

10. Example : 5
Collection of good students in a class

11. Example : 6

12. Example : 7
All colours in a rainbow

13. Example : 8
A collection of prime numbers <100

14. We come across, the usage
of sets in our everyday life

15. In the kitchen

16. Note books in a partition and all the
stationeries in another partition.

17. Which of the following collections are well defined?
(1)The collection of students (Boys) in your class.
(2) The collection of even numbers < 13
0,2, 4, 6,8, 10 and 12.
(3) The collection of districts in Tamil Nadu.
(4) The collection of all good movies.

18. (i) Descriptive form
(or)
Statement form method
(ii) Roster form
(or)
Tabular form method
(iii) set builder form
(or)
Rule form method
Representation of a Set

19. The set of even numbers less than ten
Descriptive form:
{0,2, 4, 6, 8}
Roster form :
Set builder form:
{x | x is an even number less than 10}

20. ELEMENTS :
The objects used to form a set are
called its element or its members.
Generally, the elements of a set are
written inside a pair of curly
braces and are represented by
commas. The name of the set is
always written in capital letter.
A = {v, w, x, y, z}
Here ‘A’ is the name of the set whose
elements (members) are v, w, x, y, z.

21. The elements of a set are denoted by small letters of the
English alphabets a, b, p, q, x, y, etc.
The elements of a set is written within curly brackets
“{ }”
 If x is an element of a set A or x belongs to A,
we write x A.
 If x is not an element of a set A or x does not belongs to A,
we write x A.

22. For example,
Consider the set A = {2,3,5,7} then
 2 is an element of A ; we write 2 A
 5 is an element of A ; we write 5 A
 6 is not an element of A ; we write 6 A

23. BY ,
ALEXANDER
LAKSHMI SCHOOL,
MADURAI.
CELL : 9994095939