# Does this form a topology?

by blahblah8724
Tags: intersection, topology
 P: 32 I am told that the interval (a, ∞) where a $\in$ (0, ∞) together the empty set and [0, ∞) form a topology on [0, ∞). But I thought in a topology that the intersection if any two sets had to also be in the topology, but the intersection of say (a, ∞) with (b, ∞) where a
 PF Gold P: 1,412 Given any nonepty set X, the collection (empty set, X) is a topology. It is called "trivial topology". Please, check that it indeed satisfies all the axioms of a topological space.
P: 320
 Quote by blahblah8724 I am told that the interval (a, ∞) where a $\in$ (0, ∞) together the empty set and [0, ∞) form a topology on [0, ∞). But I thought in a topology that the intersection if any two sets had to also be in the topology, but the intersection of say (a, ∞) with (b, ∞) where a
the intersection of (a,∞) and (b,∞) where a<b is (b,∞), not (a,b).

 Related Discussions Calculus & Beyond Homework 2 Topology and Analysis 2 Calculus & Beyond Homework 0 Calculus & Beyond Homework 1 Differential Geometry 5