Theorem: LO.FirstOrder.Arith.Model.subset_iff (Arithmetization/ISigmaOne/Bit.lean)

State before:
M : Type u_1
inst✝⁵ : Zero M
inst✝⁴ : One M
inst✝³ : Add M
inst✝² : Mul M
inst✝¹ : LT M
inst✝ : M ⊧ₘ* 𝐈𝚺₁
a b : M
⊢ a ⊆ b ↔ ∀ x ∈ a, x ∈ b
Tactic:
simp [HasSubset.Subset]
State after:
no goals