Question 6. In a topological space (X.r) a subset Bof X is called a 7- open subset of X if Bc(B)u(B). The family of all y-open subsets of X is denoted by 0(X). Show that 0(X) is closed under arbitrary union.

Question 6. In a topological space (X.r) a subset Bof X is called a 7- open subset of X if Bc(B)u(B). The family of all y-open subsets of X is denoted by 0(X). Show that 0(X) is closed under arbitrary union.

Elements Of Modern Algebra

8th Edition

ISBN:9781285463230

Author:Gilbert, Linda, Jimmie

Publisher:Gilbert, Linda, Jimmie

Chapter4: More On Groups

Section4.5: Normal Subgroups

Problem 36E

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