Theorem: Matroid.Indep.skew_iff_disjoint (Matroid/Modular.lean)

State before:
ι : Type u_1
α : Type u_2
M : Matroid α
B I J X X' Y Y' F : Set α
Xs Ys Js Is : ι → Set α
i j : ι
e f : α
h : M.Indep (I ∪ J)
⊢ M.Skew I J ↔ Disjoint I J
Tactic:
rw [← pairwise_disjoint_on_bool, Skew, Indep.skewFamily_iff_pairwise_disjoint]
State after:
ι : Type u_1
α : Type u_2
M : Matroid α
B I J X X' Y Y' F : Set α
Xs Ys Js Is : ι → Set α
i j : ι
e f : α
h : M.Indep (I ∪ J)
⊢ M.Indep (⋃ i, bif i then I else J)

State before:
ι : Type u_1
α : Type u_2
M : Matroid α
B I J X X' Y Y' F : Set α
Xs Ys Js Is : ι → Set α
i j : ι
e f : α
h : M.Indep (I ∪ J)
⊢ M.Indep (⋃ i, bif i then I else J)
Tactic:
rwa [union_eq_iUnion] at h
State after:
no goals