English
The realization for toPrenex coincides with the realization of the original formula.
Русский
Реализация формулы toPrenex совпадает с реализацией исходной формулы.
LaTeX
$$$\forall φ\;Realize(φ.toPrenex) = Realize(φ)$$$
Lean4
@[simp]
theorem realize_toPrenex (φ : L.BoundedFormula α n) {v : α → M} :
∀ {xs : Fin n → M}, φ.toPrenex.Realize v xs ↔ φ.Realize v xs := by
induction φ with
| falsum => exact Iff.rfl
| equal => exact Iff.rfl
| rel => exact Iff.rfl
| imp f1 f2 h1 h2 =>
intros
rw [toPrenex, realize_toPrenexImp f1.toPrenex_isPrenex f2.toPrenex_isPrenex, realize_imp, realize_imp, h1, h2]
| all _ h =>
intros
rw [realize_all, toPrenex, realize_all]
exact forall_congr' fun a => h