Cardinal Number of a Set

The cardinal number of a finite set A is considered when the numbers of distinct members of the set and it is being denoted by n(Z). The cardinal number of the empty set φ  zero ‘0’, because φ has zero members. So, n (φ) = 0, and the cardinal number of an infinite set can’t be found because, this kind of set has countless members.

If the set ‘Z’ is written in tabular form, as shown –

Example – 1) If Z = { -5,-4, -3, -2, -1, 0, 1, 2, 3, 4 },

          then n(Z) = 10

If  Z = [ x/x is a letter of the word BANGALORE ],

Tabular form, Z = { B, A, N, G, L, O, R, E }

          So, n(Z) = 8

If ‘Z’ is a set and if n(Z) = 1, we call the set ‘Z’ a Singleton Set

If, n(Z) = 2, we can call set ‘Z’ is Pair set