Theorem: Matroid.Indep.encard_le_erk (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
hI : M.Indep I
⊢ I.encard ≤ M.erk
Tactic:
rw [← hI.er, erk_eq_er_ground]
State after:
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
hI : M.Indep I
⊢ M.er I ≤ M.er M.E

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
hI : M.Indep I
⊢ M.er I ≤ M.er M.E
Tactic:
exact M.er_mono hI.subset_ground
State after:
no goals