Bourbaki

Corollary

Tag 03OQ, permanent. Cite it as [Bourbaki, Tag 03OQ].

Theory of Sets, chapter III, § 7. Inverse limits and direct limits

Let (E′αλ,f′βαμλ)(\mathrm{{E}'}^\lambda_\alpha, {f'}^{\mu\lambda}_{\beta\alpha}) be another direct system of sets relative to I×L\mathrm{I} \times \mathrm{L}, and for each (α,λ)∈I×L(\alpha, \lambda) \in \mathrm{I} \times \mathrm{L} let uαλu_\alpha^\lambda be a mapping of Eαλ\mathrm{E}_\alpha^\lambda into E′αλ\mathrm{{E}'}^\lambda_\alpha, such that the uαλu_\alpha^\lambda form a direct system of mappings. Then we have

(33)

lim→⁡α, λuαλ=lim→⁡λ (lim→⁡αuαλ).\varinjlim_{\alpha,\ \lambda} u_\alpha^\lambda = \varinjlim_{\lambda}\ (\varinjlim_{\alpha} u_\alpha^\lambda).

We leave the verification to the reader.

Bourbaki sets the proof directly after the statement, and the corpus does not separate them, so what is above is the statement and its proof together.

Cited by

Nothing.

Cites

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Transcribed from the printed edition, 2004, Springer. Not translated.