Question

IF A and b are two sets with n elements in common, then the number of elements common in a×b and b×a is
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Answer 1

Answer:

Let A and B be two non-empty sets heaving n elements in common, then we have 

(A×B)∩(C×D)=(A∩C)×(B∩D)

It is given that n(A∩B)=n elements 

Now n[(A∩B)×(B∩A)]=n.n=n2 elements

Hence, A×B and B×A have n2 elements in common .

Answer 2

Answer:

It's right mate which is written above.... I ☺☺☺☺