Bourbaki

Corollary 4

Tag 05S1, permanent. Cite it as [Bourbaki, Tag 05S1].

Algebra, chapter II, § 7. Vector spaces

For every subspace F of a vector space E, dim⁡F≤dim⁡E\dim F \leq \dim E; if E is finite dimensional, the relation dim⁡F=dim⁡E\dim F = \dim E is equivalent to F=EF = E.

The first assertion is obvious from (3); further, if dim⁡E\dim E is finite, the relation dim⁡F=dim⁡E\dim F = \dim E implies dim⁡(E/F)=0\dim(E/F) = 0 by (3) and a vector space of dimension 0 reduces to 0.

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

Cited by

Cites

Nothing.

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