exact ⟨by simp [MapsTo], Subtype.val_injective.injOn, by simp [SurjOn, Subset.rfl]⟩
α : Type u_1
β : Type u_2
f : α → β
E✝ I✝ s : Set α
M✝ : Matroid α
N✝ : Matroid β
E X I : Set α
M N : Matroid α
⊢ BijOn Subtype.val (M.E ↓∩ (M ↾ M.E).E) (M ↾ M.E).E
no goals