exact ExistsUnique.intro y (by simp) (by rintro _ ⟨_, rfl⟩; simp)
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
y x : M
⊢ ∃! y_1, x = x ∧ y_1 = y
no goals