Theorem: ClMatroid.cl_subset_ground (Matroid/Constructions/ClosureAxioms.lean)

State before:
α : Type u_1
I B X✝ : Set α
M : ClMatroid α
X : Set α
⊢ M.cl X ⊆ M.E
Tactic:
rw [← M.cl_inter_inter_ground]
State after:
α : Type u_1
I B X✝ : Set α
M : ClMatroid α
X : Set α
⊢ M.cl (X ∩ M.E) ∩ M.E ⊆ M.E

State before:
α : Type u_1
I B X✝ : Set α
M : ClMatroid α
X : Set α
⊢ M.cl (X ∩ M.E) ∩ M.E ⊆ M.E
Tactic:
apply inter_subset_right
State after:
no goals