Metamath Proof Explorer


Theorem sdrgsubrg

Description: A sub-division-ring is a subring. (Contributed by SN, 19-Feb-2025)

Ref Expression
Assertion sdrgsubrg ⊢ A ∈ SubDRing ⁡ R → A ∈ SubRing ⁡ R

Proof

Step Hyp Ref Expression
1 issdrg ⊢ A ∈ SubDRing ⁡ R ↔ R ∈ DivRing ∧ A ∈ SubRing ⁡ R ∧ R ↾ 𝑠 A ∈ DivRing
2 1 simp2bi ⊢ A ∈ SubDRing ⁡ R → A ∈ SubRing ⁡ R