Mathematics in the Modern World

1. LET'S LEARN!

2. A set is a collection of well-defined objects that
contains no duplicates. The objects in the set are
called the elements of the set. To describe a set, we
use braces { }, and use capital letters to represent it.
What is a set?

3. Types of Sets
1. Finite and infinite set
2. Empty set
3. Singleton set
4. Equal sets
5. Equivalent sets
6. Universal set
7. Subsets(proper and improper)
8. Power set

4. Finite and
Infinite Set
Examples:
1. Set A = {2,4,6,8,10} — finite set
2. Set B = {1,3,5,7,9…} — infinite set
A finite set contains elements that can be counted and
terminates at certain natural number. While the infinite
set whose elements can't be estimated, but has some
figure or number, which is large to precise in a set.

5. Empty Set The empty set, or null set, ∅ or { }, which has
no members/elements at all.
Example:
Set C = { }

6. Singleton Set
("Singleton of a")
Example:
Set D = {10}
A set with only one member is called a singleton or
a singleton set.

7. Equal Sets Two sets are equal if they contain exactly the
same elements.
Example:
{2,4,6,8} = {2,4,6,8}

8. Equivalent Sets
Examples:
1. {a, b, c}, {1,2,3}
2. {1,4,3}, {2,5,4}
Two sets are equivalent if they contain the same
number of elements.

9. Universal Set A set that contains all the elements
considered in a particular situation and
denoted by U.
Example:
a. Suppose we list the digits only. Then, U =
{0,1,2,3,4,5,6,7,8,9}, since U includes all
the digits.
b. Suppose we consider the whole numbers.
Then, U ={0,1,2,3,…} since U contains all
whole numbers.

10. Subsets
Examples:
1. A = {7,9} is a subset of B = {6,9,7}
2. D = {10,8,6} is a subset of G = {10,8,6}
A set A is called a subset of set B if every element
of A is also an element of B. "A is a subset of B is
written as A ⊂ B.
A proper subset is a subset that is not equal to the
original set, while the improper subset is opposite
of it.
Example:
Given {3,5,7} then the proper subset are { }, {5,7},
{3,5}, {3,7}.
The improper subset is {3,5,7}.

11. Power Set It is the family of all the subsets of A denoted
by Power (A).
Example:
Given set A = {x, y}, the Power (A) = {∅, {x}, {y},
{x, y} or {x|x is a subset of A.

12. THANK YOU