,.,.i have this silly intuition.,.,.my intuition says that boundary(A intersection B) is a subset of boundary(A) and boundary(B),.,i know im wrong,.,.hahahah
,.,.i have this silly intuition.,.,.my intuition says that boundary(A intersection B) is a subset of boundary(A) and boundary(B),.,i know im wrong,.,.hahahah
Yes, you are wrong . In with the usual topology choose . Then, and .