Aynur KESKİN, Şaziye YÜKSEL, Takashi NOIRI

ON /-EXTREMALLY DISCONNECTED SPACES

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 : akeskin@email.selcuk.edu.tr, syuksel@selcuk.edu.tr, t.noiri@nifty.com

Communications Faculty of Sciences University of Ankara Series A1 Mathematics and Statistics-Cover

ISSN: 1303-5991
Yayın Aralığı: Yılda 4 Sayı
Başlangıç: 1948
Yayıncı: Ankara Üniversitesi

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