fact: Definition mulc (x y : C) := let: a +i* b := x in let: c +i* d := y in ((a * c) - (b * d)) +i* ((a * d) + (b * c)).
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)