proposition: Lemma addcJ (z : R[i]) : z + z^*%C = 2%:R * (Re z)%:C.
proof: Proof. by rewrite ReJ_add mulrC mulfVK ?pnatr_eq0. Qed.
imports: HB(structures) mathcomp.ssreflect.ssreflect mathcomp(ssrfun ssrbool eqtype ssrnat seq choice fintype) mathcomp(bigop order ssralg ssrint div ssrnum rat poly closed_field) mathcomp(polyrcf matrix mxalgebra tuple mxpoly zmodp binomial realalg) mathcomp(mxpoly)