proposition: Lemma cvgy_esups u : u @ \oo --> +oo -> esups u @ \oo --> +oo.
proof: Proof. move=> /cvgeN/cvgNy_einfs/cvgeN; rewrite einfsN. by under eq_cvg do rewrite /= oppeK. Qed.
imports: mathcomp(all_ssreflect ssralg ssrint ssrnum matrix) mathcomp(interval rat) mathcomp(mathcomp_extra boolp classical_sets functions) mathcomp(set_interval) reals ereal signed topology normedtype landau