Bourbaki

Corollary

Tag 08DS, permanent. Cite it as [Bourbaki, Tag 08DS].

Functions of a Real Variable, chapter V, § 1. COMPARISON OF FUNCTIONS ON A FILTERED SET

If VV is a normed algebra, if f1,f2f_1, f_2 are two functions in H(F,V)\mathscr{H}(\mathfrak{F}, V), and g1,g2g_1, g_2 are two functions in H(F,R)\mathscr{H}(\mathfrak{F}, \mathbf{R}), then the relations f1≼g1,f2≼g2f_1 \preccurlyeq g_1, f_2 \preccurlyeq g_2 imply f1f2≼g1g2f_1 f_2 \preccurlyeq g_1 g_2.

The relation f≼gf \preccurlyeq g between functions in H(F,V)\mathscr{H}(\mathfrak{F}, V) is transitive by prop. 1; since it is reflexive the relation "*f \preccurlyeq g and g \preccurlyeq f*" is an equivalence relation on H(F,V)\mathscr{H}(\mathfrak{F}, V) (Set Theory, II, p. 113).

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 volume. Not translated.