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On Darboux weak retractions
Karlova Olena 1,2
1 Department of Mathematical Analysis, Yuriy Fedkovych Chernivtsi National University, Chernivtsi, 58000, Ukraine
2 Jan Kokhanowski University, Kielce, 25-001, Poland
Keywords: connected continuous subset, Darboux reflection, retract
Abstract

We prove that any connected subset $F$ of a connected space $X$ with $|F| = \mathfrak{c} $ is a Darboux retract of $X$ if there exists a Darboux function $f : X → [0,1]$ such that $F = f^{-1} (0).$  We also show that any connected subset $E$ of a metrizable separable space $X$ is a weak Darboux retract of $X$ if the complement $X$ \ $E$ has no isolated points.

References

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Cite
ACS Style
Karlova, O. On Darboux weak retractions. Bukovinian Mathematical Journal. 2016, 3
AMA Style
Karlova O. On Darboux weak retractions. Bukovinian Mathematical Journal. 2016; 3(3-4).
Chicago/Turabian Style
Olena Karlova. 2016. "On Darboux weak retractions". Bukovinian Mathematical Journal. 3 no. 3-4.
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