Connectrdness concepts PDF

Summary

This document discusses the concept of connectedness in topology. It defines disconnected spaces, provides examples, and includes remarks about discrete topology. It touches upon open sets and close sets within a topological space.

Full Transcript

***[Connectrdness]*** Disconnected space , when (X,Ƭ) is topological space \ [*x* = *A* ∪ *B*]{.math.display}\ \ [*A* ≠ ⌀ , *B* ≠ ⌀]{.math.display}\ \ [*A*, *B* ∈ *τ*]{.math.display}\ \ [*A* ∩ *B* = ⌀]{.math.display}\ (X,Ƭ) is disconnected space , when (X,Ƭ) is topogical space [*X* ≠ *A* ∪ *...

***[Connectrdness]*** Disconnected space , when (X,Ƭ) is topological space \ [*x* = *A* ∪ *B*]{.math.display}\ \ [*A* ≠ ⌀ , *B* ≠ ⌀]{.math.display}\ \ [*A*, *B* ∈ *τ*]{.math.display}\ \ [*A* ∩ *B* = ⌀]{.math.display}\ (X,Ƭ) is disconnected space , when (X,Ƭ) is topogical space [*X* ≠ *A* ∪ *B*]{.math.inline} \ [*A*, *B* ∈ *Ƭ*]{.math.display}\ \ [*A* ∩ *B* ≠ 0]{.math.display}\ \ [*A* ≠ ⌀ = *B*]{.math.display}\ **Example** [*x* = {1,2,3}]{.math.inline} Ƭ= { x,Ф,{1} } is (x,Ƭ) connected X=X [ ∪ {1}             *But* *x* ∩ {1} ≠ ⌀]{.math.inline} (x,Ƭ) is connected space If [*A*, *A*^*C*^ ∈ *τ* → (*x*,*τ*) is disconnected]{.math.inline} [*A* ∪ *A*^*C*^ = *x*]{.math.inline} \ [*A* ∩ *A*^*C*^ = ⌀]{.math.display}\ **[Remarks]** : (x,D) → disconnected space , D= discrete topology ([*x*, *τ*) *is* *topological* *apace*             *τ* = *ʄ* ]{.math.inline} Open set =close set [*A*, *A*^*C*^ ∈ *τ*]{.math.inline} [(*x*,*τ*)disconnected]{.math.inline} ([*x*, *I*)            *x* = *x* ∪ ⌀]{.math.inline} , I = inscrete topology [*β* = ⌀              ∴ *τ* *is* *connected*]{.math.inline} **Example ։**Let [*τ* = {*x*,⌀,{1},{2,3}}]{.math.inline} ([*x*, *τ*) *topo* *space* :]{.math.inline} Is Ƭ connected or disconnected A[ ∪ *B* = {1} ∪ {2,3} = {1,2,3}]{.math.inline} (X,Ƭ) is disconnected space [REMARKS ] *Let T be clopen subset of R , then either T=R or T= Ø.* *Let (X, τ ) be a topological space. Then it is said to be connected if the only clopen subsets of X are X and Ø.* *The topological space R is connected.*

Use Quizgecko on...
Browser
Browser