ON /-EXTREMALLY DISCONNECTED SPACES

Year 2007, , 33 - 40, 01.02.2007

Aynur Keskin Şaziye Yüksel Takashi Noırı

https://doi.org/10.1501/Commua1_0000000195

Abstract

Abstract. We have introduced and investigated the notion of I-extremal disconnectedness on ideal topological spaces. First, we found that the notions of
extremal disconnectedness and I-extremal disconnectedness are independent
of each other. About the letter one, we observed that every open subset of
an I-extremally disconnected space is also an I-extremally disconnected space.
And also, in extremally disconnectedness spaces we have shown that I-open
set is equivalent almost I-open and every -I-open set is preopen. Finally,
we have shown that B-I-continuity( resp. pre-I-continuity, I-continuity ) is
equivalent to semi-I-continuity( resp. strongly -I-continuity, almost strongly
I-continuity ) if the domain is I-exteremally disconnected

Keywords

W eak regular-I-closed sets, I-open sets, I-extremally disconnectedspaces, topological ideal

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• Current address : Aynur KESKIN,Selcuk University, Department of Mathematics, 42075 Campus
• Konya TURKEY, Sazıye YUKSEL, Selcuk University, Department of Mathematics, 42031 Campus
• Konya TURKEY, Takashi NOIRI,2949-1 Shiokita-cho, Hinagu Yatsushiro-shi, Kumamoto-ken 869-5142 JAPAN E-mail address : [e-mail], [e-mail], [e-mail]