Formula For Cardinal Number of Set

Cardinal Number of Set

• If A and B are two disjoint subsets of universal set U then n(A∪B) = n(A)+n(B)
• If A and B are overlapping subsets of universal subsets of U then n(A∪B)= n(A)+n(B)-n(A∩B)
• If A, B and C  are overlapping subsets of universal subsets of U then n(A∪B∪C)= n(A)+n(B)+n(C)-n(A∩B)-n(B∩C)-n(A∩C)+n(A∩B∩C)
• n(AUB)' = n(U)-n(A∪B)
• n(A∪B∪C)'=n(U)- n(A∪B∪C)