simpa [HSemiformula.extd] using h.iff e
case mkDelta
L : Language
inst✝⁷ : L.ORing
ξ : Type v
n : ℕ
M : Type u_1
inst✝⁶ : Zero M
inst✝⁵ : One M
inst✝⁴ : Add M
inst✝³ : Mul M
inst✝² : LT M
inst✝¹ : Structure L M
inst✝ : Structure.ORing L M
m : ℕ
e : Fin n → M
a✝¹ : HSemiformula ℒₒᵣ Empty n (𝚺, m)
a✝ : HSemiformula ℒₒᵣ Empty n (𝚷, m)
h : ProperOn M (a✝¹.mkDelta a✝)
⊢ (Semiformula.Evalbm M e) (HSemiformula.extd L (a✝¹.mkDelta a✝)).sigma.val ↔
    (Semiformula.Evalbm M e) (HSemiformula.extd L (a✝¹.mkDelta a✝)).pi.val
no goals