Question

If A = {2, 3, 4} and B = {3, 4, 5, 6} then the number of elements common to A x B and B x A is *​

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=n  

2

 elements

Hence, A×B and B×A have n  

2

 elements in common .

Step-by-step explanation:

Answer 2

See the picture like the way you can do your answer:-)