1.

Let A and B be two sets having 3 and 6 elements respectively. Write the minimum number of elements that .A⋃B can have

Answer»

Here, 

n(A) = 3 and n(B) = 6 

Now, 

n(A⋃B) = n(A) + n(B) - n(A⋂B) 

= 3 + 6 - n(A⋂B) 

= 9 - n(A⋂B) 

So,

n(A⋃B) is minimum whenever n(A⋂B) is maximum and it is possible only when A⊂B 

Now,A⊂B then max(n(A⋂B)) = n(A) = 3. 

∴ min(n(A⋃B) ) = 9-3 = 6



Discussion

No Comment Found

Related InterviewSolutions