Theorem
|The intersection of a closed setwith a compact setis compact.
Proof
Letbe an open cover ofso that
Thenand sinceis closed is an open cover of
is compact so a finite subcoverof A exists.
Henceandis compact.
Theorem
|The intersection of a closed setwith a compact setis compact.
Proof
Letbe an open cover ofso that
Thenand sinceis closed is an open cover of
is compact so a finite subcoverof A exists.
Henceandis compact.