proposition: Corollary oppℝ_Req_involutive_realizer : forall e, oppℝ_Req_involutive↓e ⊩ ∀x, Cauchy x → (- - x ≡ x)%Re.
proof: Proof. intro e. start. apply Eeq_implies_Req_realizer. find. now do 2 (start; apply oppℝ_Cauchy_realizer; find). start. apply oppℝ_Eeq_involutive_realizer. find. Qed.
imports: QArith Psatz ClassicalRealizability.Kbase ClassicalRealizability.Rationals ClassicalRealizability.Real_definitions ClassicalRealizability.Real_relations