A separate continuous function not somewhat continuous

Wojciech Bielas
https://orcid.org/0000-0002-4903-4872


Abstract

We construct a separately continuous function f:ℚ×ℚ→[0,1] and a dense subset D⊆ℚ×ℚ such that f[D] is not dense in f[ℚ×ℚ], in other words, f is separately continuous and not somewhat (feebly) continuous.


Keywords

separate continuity; somewhat continuous function

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Published : 2021-10-11


BielasW. (2021). A separate continuous function not somewhat continuous. Annales Mathematicae Silesianae, 36(1), 26-29. Retrieved from https://journals.us.edu.pl/index.php/AMSIL/article/view/13458

Wojciech Bielas  wojciech.bielas@us.edu.pl
Instytut Matematyki, Uniwersytet Śląski w Katowicach  Poland
https://orcid.org/0000-0002-4903-4872



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