Points of Continuity of Quasi-Continuous Functions

Marzieh Neghaban; Alireza Kamel Mirmostafaee

doi:10.2478/tmmp-2020-0017

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Points of Continuity of Quasi-Continuous Functions

Tatra Mountains Mathematical Publications

Volume 76 (2020): Issue 1 (December 2020)

By: Marzieh Neghaban and Alireza Kamel Mirmostafaee

Open Access

|Nov 2020

Abstract

We study points of joint continuity of multi-variable separately quasi-continuous functions which are continuous with respect to one variable. We will show that the assumption of complete regularity in the paper of V. Maslyuchenko et al in ”Tatra Mt. Math. Pub. 68, (2017), 47–58” can be removed in some situations. Moreover, we use a topological game argument to prove that the set of points of continuity of functions with closed graph into ωΔ-spaces is a G_δ subset of its domain provided that its domain is a W-space.

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Articles in this issue

DOI: https://doi.org/10.2478/tmmp-2020-0017 | Journal eISSN: 1338-9750 | Journal ISSN: 1210-3195

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Language: English

Page range: 53 - 62

Submitted on: Jul 8, 2019

Published on: Nov 4, 2020

Published by: Slovak Academy of Sciences, Mathematical Institute

In partnership with: Paradigm Publishing Services

Publication frequency: 1 issue per year

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© 2020 Marzieh Neghaban, Alireza Kamel Mirmostafaee, published by Slovak Academy of Sciences, Mathematical Institute
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Volume 76 (2020): Issue 1 (December 2020)