Theorem: Matroid.restrict_er_eq (Matroid/Rank.lean)

State before:
α : Type u_1
ι : Type u_2
M✝ N : Matroid α
I B X X' Y Y' Z R : Set α
n : ℕ∞
e f : α
M : Matroid α
h : X ⊆ R
⊢ (M ↾ R).er X = M.er X
Tactic:
rw [restrict_er_eq', inter_eq_self_of_subset_left h]
State after:
no goals