proposition: Lemma invR1 : (1^-1 : R) == 1.
proof: Proof. by have:= divRR neqR10; rewrite mul1R. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div order) mathcomp(ssralg ssrnum ssrint rat intdiv) Coq(Morphisms Setoid) fourcolor(real realsyntax)