📚 Recommended Mathematics Books

Topology (Munkres)  |  General Topology (Engelking)  |  Counterexamples in Topology  |  Rudin's Analysis

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In this online article I’ve proved:

Theorem $latex \mathrm{dom}\, (\mathsf{RLD})_{\mathrm{in}} f = \mathrm{dom}\, f$ and $latex \mathrm{im}\, (\mathsf{RLD})_{\mathrm{in}} f = \mathrm{im}\, f$ for every funcoid $latex f$.

and its easy consequence:

Proposition $latex \mathrm{dom}\, (\mathsf{RLD})_{\Gamma} f = \mathrm{dom}\, f$ and $latex \mathrm{im}\, (\mathsf{RLD})_{\Gamma} f = \mathrm{im}\, f$ for every funcoid $latex f$.