Metamath Proof Explorer


Theorem prdsmulrcl

Description: A structure product of rings has closed binary operation. (Contributed by Mario Carneiro, 11-Mar-2015) (Proof shortened by AV, 30-Mar-2025)

Ref Expression
Hypotheses prdsmulrcl.y ⊢ Y = S ⨉ 𝑠 R
prdsmulrcl.b ⊢ B = Base Y
prdsmulrcl.t ⊢ · ˙ = ⋅ Y
prdsmulrcl.s ⊢ φ → S ∈ V
prdsmulrcl.i ⊢ φ → I ∈ W
prdsmulrcl.r ⊢ φ → R : I ⟶ Ring
prdsmulrcl.f ⊢ φ → F ∈ B
prdsmulrcl.g ⊢ φ → G ∈ B
Assertion prdsmulrcl ⊢ φ → F · ˙ G ∈ B

Proof

Step Hyp Ref Expression
1 prdsmulrcl.y ⊢ Y = S ⨉ 𝑠 R
2 prdsmulrcl.b ⊢ B = Base Y
3 prdsmulrcl.t ⊢ · ˙ = ⋅ Y
4 prdsmulrcl.s ⊢ φ → S ∈ V
5 prdsmulrcl.i ⊢ φ → I ∈ W
6 prdsmulrcl.r ⊢ φ → R : I ⟶ Ring
7 prdsmulrcl.f ⊢ φ → F ∈ B
8 prdsmulrcl.g ⊢ φ → G ∈ B
9 ringssrng ⊢ Ring ⊆ Rng
10 fss ⊢ R : I ⟶ Ring ∧ Ring ⊆ Rng → R : I ⟶ Rng
11 6 9 10 sylancl ⊢ φ → R : I ⟶ Rng
12 1 2 3 4 5 11 7 8 prdsmulrngcl ⊢ φ → F · ˙ G ∈ B