For any two points there exists two open sets and such that and , and and . A space satisfying this axiom is known as a T1-space.
See alsoHausdorff Axioms, Separation Axioms, T1-Space
This entry contributed by Margherita Barile
Explore with Wolfram|Alpha
Cite this as:
Barile, Margherita. "T_1-Separation Axiom." From MathWorld--A Wolfram Web Resource, created by Eric W. Weisstein. https://mathworld.wolfram.com/T1-SeparationAxiom.html