Accumulation point: Let X be a topological space. A point p ∊ X is an accumulation point or limit point (also called cluster point or derived point) of a subset A of X if and only if every open set G containing p contains a point A different from p, ...

Read More »## Topological Spaces | Topology

Definition: Let X be a non empty set. A class T of subsets of X is a topology on X if and only if T satisfies the following axioms. [O1] X and ∅ belong to T. [O2] The union of any number of sets in T belongs to T. [O3] ...

Read More »## Continuous function|Lecture-1

Definition: Let (X, T) and (Y, T*) be topological spaces. A function f from X into Y is continuous relative to T and T*, Or, T-T* continuous or simply continuous, if and only if the inverse image f-1[H] of every T* open subset H of Y is a T – ...

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