exact relRank_self_eq_zero
case pos
α : Type u_1
A B I J X : Set α
x : α
M : RankMatroid α
hI : I ⊆ X
hI_indep : M.Indep I
hI_max : I ∈ maximals (fun x x_1 => x ⊆ x_1) {S | M.Indep S ∧ S ⊆ X}
hXI : X = I
⊢ M.relRank I I = 0
no goals