1. The Baire category theorem - Aarhus Universitet
1. The Baire category theorem - Aarhus Universitet
1. The Baire category theorem - Aarhus Universitet
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Definition of first and second <strong>category</strong><br />
Example: A metric space X with metric d is a topological space:<br />
<strong>The</strong> open sets, τ, consists of the subsets U of X which satisfies the<br />
following condition:<br />
∀x ∈ U ∃δ > 0 : {y ∈ X : d(y,x) < δ} ⊆ U.<br />
Klaus Thomsen <strong>1.</strong> <strong>The</strong> <strong>Baire</strong> <strong>category</strong> <strong>theorem</strong>