Metamath Proof Explorer


Theorem submmulgcl

Description: Closure of the group multiple (exponentiation) operation in a submonoid. (Contributed by Mario Carneiro, 13-Jan-2015)

Ref Expression
Hypothesis submmulgcl.t ⊢ ∙ ˙ = ⋅ G
Assertion submmulgcl ⊢ S ∈ SubMnd ⁡ G ∧ N ∈ ℕ 0 ∧ X ∈ S → N ∙ ˙ X ∈ S

Proof

Step Hyp Ref Expression
1 submmulgcl.t ⊢ ∙ ˙ = ⋅ G
2 eqid ⊢ Base G = Base G
3 eqid ⊢ + G = + G
4 submrcl ⊢ S ∈ SubMnd ⁡ G → G ∈ Mnd
5 2 submss ⊢ S ∈ SubMnd ⁡ G → S ⊆ Base G
6 3 submcl ⊢ S ∈ SubMnd ⁡ G ∧ x ∈ S ∧ y ∈ S → x + G y ∈ S
7 eqid ⊢ 0 G = 0 G
8 7 subm0cl ⊢ S ∈ SubMnd ⁡ G → 0 G ∈ S
9 2 1 3 4 5 6 7 8 mulgnn0subcl ⊢ S ∈ SubMnd ⁡ G ∧ N ∈ ℕ 0 ∧ X ∈ S → N ∙ ˙ X ∈ S