Hint Rewrite <- @MakeSequentCalculus_IntuitionisticPropositionalLogic using (instantiate_must_succeed; apply Typeclass_Rewrite_I): AddSC.
Section DerivableRulesFromAxiomatization1.
Context {L: Language}
{minL: MinimunLanguage L}
{pL: PropositionalLanguage L}
{Gamma: ProofTheory L}
{minAX: MinimunAxiomatization L Gamma}
{ipGamma: IntuitionisticPropositionalLogic L Gamma}.

Lemma solve_orp_impp: forall x y z: expr,
|-- x --> z -> |-- y --> z -> |-- x || y --> z.