Theorem: Matroid.Skew.mono (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.Skew X Y
hX : X' ⊆ X
hY : Y' ⊆ Y
⊢ (fun i => bif i then X' else Y') false ⊆ bif false then X else Y
Tactic:
simpa
State after:
no goals

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.Skew X Y
hX : X' ⊆ X
hY : Y' ⊆ Y
⊢ (fun i => bif i then X' else Y') true ⊆ bif true then X else Y
Tactic:
simpa
State after:
no goals