Question

if a b c are subsets of universal set u prove that (a union b)' = a' intersection b'​

Answer 1

Answer:

Given n(U)=692,n(B)=230,n(C)=370,n(B∩C)=20, n(A∩B

′

∩C

′

)=10

n(A

′

∩B

′

∩C

′

)=n((B

′

∩C

′

)∩A

′

)

n(A

′

∩B

′

∩C

′

)=n((B∪C)

′

∩A

′

)

=n((B∪C)

′

)−n((B∪C)

′

∩A)

=n(U)−n(B∪C)−n(A∩B

′

∩C

′

)

=n(U)−n(B)−n(C)+n(B∩C)−n(A∩B

′

∩C

′

)

=692−230−370+20−10=102