Question

the intersection of any two disjoint sets is a null set .justify​

Answer 1

Disjoint sets are those sets which have no element as common. For example, let's suppose there is a set A = {x : x is an even natural number} and a set B = {y : y is a odd natural number}. Clearly, there is no common element between set A and B as there is no natural number which is both even and odd. That is, set A and set B are disjoint sets.

Now, intersection of two sets is the set of elements which are common to both sets. Since, two disjoint sets have no elements common, their intersection will have nothing. That is, their intersection will be a null set (Ф, phi)