Theorem: Matroid.rFin.rFin_diff_iff (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
hX : M.rFin X
⊢ M.rFin (Y \ X) ↔ M.rFin Y
Tactic:
rw [← hX.rFin_union_iff, union_diff_self, hX.rFin_union_iff]
State after:
no goals