proposition: Lemma RltbP r1 r2 : reflect (r1 < r2) (Rltb r1 r2).
proof: Proof. rewrite /Rltb /Rleb; apply: (iffP idP); case: Rle_dec=> //=. - by case=> // r1Er2 /eqP[]. - by move=> _ r1Lr2; apply/eqP/Rlt_not_eq. by move=> Nr1Lr2 r1Lr2; case: Nr1Lr2; left. Qed.
imports: Rdefinitions Raxioms RIneq Rbasic_fun Zwf Epsilon FunctionalExtensionality Ranalysis1 Rsqrt_def Rtrigo1 Reals mathcomp(all_ssreflect ssralg poly mxpoly ssrnum) HB(structures)