Theorem: l1_2_20_i' (AlgebraI/Subgroups.lean)

State before:
G : Type u_1
inst✝ : Group G
g : G
h : IsOfFinOrder g
⊢ ↑(Subgroup.closure {g}) = {x | ∃ i ∈ Set.Ico 0 (orderOf g), g ^ i = x}
Tactic:
ext
State after:
case h
G : Type u_1
inst✝ : Group G
g : G
h : IsOfFinOrder g
x✝ : G
⊢ x✝ ∈ ↑(Subgroup.closure {g}) ↔ x✝ ∈ {x | ∃ i ∈ Set.Ico 0 (orderOf g), g ^ i = x}

State before:
case h
G : Type u_1
inst✝ : Group G
g : G
h : IsOfFinOrder g
x✝ : G
⊢ x✝ ∈ ↑(Subgroup.closure {g}) ↔ x✝ ∈ {x | ∃ i ∈ Set.Ico 0 (orderOf g), g ^ i = x}
Tactic:
simp [Subgroup.mem_closure_singleton' h]
State after:
no goals