Section NormedModule1.
Context {K : AbsRing} {V : NormedModule K}.
Definition norm : V -> R := NormedModule.norm K _ (NormedModule.class K V).
Definition norm_factor : R := NormedModule.norm_factor K _ (NormedModule.class K V).

Lemma norm_triangle :
forall x y : V,
norm (plus x y) <= norm x + norm y.