Theorem: Matroid.Circuit.cl_diff_singleton_eq_cl (Matroid/Circuit.lean)

State before:
α : Type u_1
M : Matroid α
C C' I X K C₁ C₂ R : Set α
e✝ f x y : α
hC : M.Circuit C
e : α
he : e ∈ C
⊢ M.cl (C \ {e}) = M.cl C
Tactic:
rw [(hC.diff_singleton_basis he).cl_eq_cl]
State after:
no goals

State before:
α : Type u_1
M : Matroid α
C C' I X K C₁ C₂ R : Set α
e✝ f x y : α
hC : M.Circuit C
e : α
he : e ∉ C
⊢ M.cl (C \ {e}) = M.cl C
Tactic:
rw [diff_singleton_eq_self he]
State after:
no goals