fact: Definition pred_eq {X} (p q: X -> Prop): Prop := forall x, p x <-> q x.
imports: Coq.QArith.Qabs CoRN.model.ordfields.Qordfield CoRN.model.structures.Qpossec Coq.QArith.Qminmax Coq.setoid_ring.Ring Coq.Program.Program