Definition of Cardinality of a Set
A set may contain a single element or multiple elements. The sets having multiple elements may be countable or uncountable. In other words, a set may contain a definite number of elements or an indefinite number of elements. The Cardinality of a Set is basically the count of the number of elements present in the set.
Therefore, the Cardinality of a Set may be defined as the size of the set or the number of elements present in the set.
For example, if the number of elements present in a set is 5, then the Cardinality of the Set will be 5.
The Cardinality of an Empty set is 0 and the Cardinality of an Infinite Set is not defined.
Symbol for Cardinality of a Set
Let us consider two sets A and B as shown in the figure below.

The set A has 5 elements, i.e.,
A=\{1, 2, 3, 4, 5\}
The Cardinality of the Set A can be written as
n(A)=5
Also, as shown in the figure, set A and B has the same number of elements. For each element in set A, there is one element present in set B. Therefore, it can be said that the set A and B have same Cardinality.
\therefore n(A)=n(B)=5
Frequently Asked Questions (FAQ)
[sp_easyaccordion id=”3930″]

Hi, my name is Abdur Rohman. By profession, I am an Electrical Engineer. I am also a part time Teacher, Blogger and Entrepreneur. The reason for starting this Website or Blog is mainly because I love teaching. Whenever I get time, I teach students/aspirants irrespective of their class or standards. More Info