Bourbaki

Remark

Tag 05MZ, permanent. Cite it as [Bourbaki, Tag 05MZ].

Algebra, chapter II, § 2. Modules of linear mappings. Duality

(1) Theorem 2 allows us, for every submodule F' of F, to identify Hom(E, F') with a sub-Z\mathbf{Z}-module of Hom(E, F). When this identification is made, then, for every family (Mλ)(M_\lambda) of submodules of F

Hom⁡(E,⋂λMλ)=⋂λHom⁡(E,Mλ) \operatorname{Hom}(E, \bigcap_\lambda M_\lambda) = \bigcap_\lambda \operatorname{Hom}(E, M_\lambda)

for if u∈Hom⁡(E,F)u \in \operatorname{Hom}(E, F) belongs to each of the Hom⁡(E,Mλ)\operatorname{Hom}(E, M_\lambda), then, for all x∈Ex \in E, u(x)∈Mλu(x) \in M_\lambda for all λ\lambda and hence uu maps E into ⋂λMλ\bigcap_\lambda M_\lambda.

Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.

Cited by

Nothing.

Cites

Transcribed from the printed edition, 1998, Springer. Not translated.