Metamath Proof Explorer


Theorem srgidmlem

Description: Lemma for srglidm and srgridm . (Contributed by NM, 15-Sep-2011) (Revised by Mario Carneiro, 27-Dec-2014) (Revised by Thierry Arnoux, 1-Apr-2018)

Ref Expression
Hypotheses srgidm.b ⊢ B = Base R
srgidm.t ⊢ · ˙ = ⋅ R
srgidm.u ⊢ 1 ˙ = 1 R
Assertion srgidmlem ⊢ R ∈ SRing ∧ X ∈ B → 1 ˙ · ˙ X = X ∧ X · ˙ 1 ˙ = X

Proof

Step Hyp Ref Expression
1 srgidm.b ⊢ B = Base R
2 srgidm.t ⊢ · ˙ = ⋅ R
3 srgidm.u ⊢ 1 ˙ = 1 R
4 eqid ⊢ mulGrp R = mulGrp R
5 4 srgmgp ⊢ R ∈ SRing → mulGrp R ∈ Mnd
6 4 1 mgpbas ⊢ B = Base mulGrp R
7 4 2 mgpplusg ⊢ · ˙ = + mulGrp R
8 4 3 ringidval ⊢ 1 ˙ = 0 mulGrp R
9 6 7 8 mndlrid ⊢ mulGrp R ∈ Mnd ∧ X ∈ B → 1 ˙ · ˙ X = X ∧ X · ˙ 1 ˙ = X
10 5 9 sylan ⊢ R ∈ SRing ∧ X ∈ B → 1 ˙ · ˙ X = X ∧ X · ˙ 1 ˙ = X