Metamath Proof Explorer


Theorem domnnzr

Description: A domain is a nonzero ring. (Contributed by Mario Carneiro, 28-Mar-2015)

Ref Expression
Assertion domnnzr ⊢ R ∈ Domn → R ∈ NzRing

Proof

Step Hyp Ref Expression
1 eqid ⊢ Base R = Base R
2 eqid ⊢ ⋅ R = ⋅ R
3 eqid ⊢ 0 R = 0 R
4 1 2 3 isdomn ⊢ R ∈ Domn ↔ R ∈ NzRing ∧ ∀ x ∈ Base R ∀ y ∈ Base R x ⋅ R y = 0 R → x = 0 R ∨ y = 0 R
5 4 simplbi ⊢ R ∈ Domn → R ∈ NzRing