Points of Continuity of Quasi-Continuous Functions

Neghaban, Marzieh; Mirmostafaee, Alireza Kamel

doi:10.2478/tmmp-2020-0017

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.

References

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Points of Continuity of Quasi-Continuous Functions

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