proposition: Lemma lnV : {in Num.pos, {morph ln : x / x ^-1 >-> - x}}.
proof: Proof. move=> x x0; apply: expR_inj; rewrite lnK// ?expRN ?lnK//. by move: x0; rewrite !qualifE/= invr_gt0. Qed.
imports: mathcomp(all_ssreflect ssralg ssrint ssrnum matrix) mathcomp(interval rat) mathcomp(boolp classical_sets functions) mathcomp(mathcomp_extra) reals ereal signed topology normedtype landau sequences derive realfun itv convex