Show that for any set X its power set PXis not emptySolution
Solution
We have to prove that power set of any set is not empty.
Let x be any set.
X can be a null set or contains some elements
If X is a null set, then again phi, a null set is a subset of X HenceP(x) contains null set.
So even if X is a null set P(X) is not empty
If X is not a null set, then X contains atleast one element a.
The set {a}, {} are elements of power set P(X)
Hence whether X is a null set or contains any element, P(X) cannot be empty
