fact: Definition ln_id' x (H : 0 < x <= 1) := derive_pt ln_id x (pderivable_ln_id_xle1 H).
imports: mathcomp(all_ssreflect ssralg ssrnum) mathcomp(Rstruct) Reals Lra ssrR realType_ext Reals_ext Ranalysis_ext logb convex