proposition: Lemma root_opp_algcreal (x : algcreal) : ((annul_creal (sub_algcreal (cst_algcreal 0) x)).[- x] == 0)%CR.
proof: Proof. by apply: is_root_annul_creal; rewrite /= add_0creal. Qed.
imports: HB(structures) mathcomp.ssreflect.ssreflect mathcomp(ssrfun ssrbool eqtype ssrnat seq choice fintype) mathcomp(bigop order ssralg ssrnum ssrint rat poly polydiv polyorder) mathcomp(perm matrix mxpoly polyXY binomial generic_quotient) mathcomp(cauchyreals separable zmodp bigenough)