Search results with tag "Notes on introductory point set topology"

Notes on Introductory Point-Set Topology

third definition, equivalent to these two, that is the one we want here. This definition is expressed in terms of the notion of an open set in R, generalizing the familiar idea of an open interval (a,b). Definition. A subset O of R is open if for each point x ∈ O there exists an interval (a,b) that contains x and is contained in O.

  Notes, Points, Third, Introductory, Topology, Notes on introductory point set topology