Metamath Proof Explorer


Theorem idlsrgmulrval

Description: Value of the ring multiplication for the ideals of a ring R . (Contributed by Thierry Arnoux, 1-Jun-2024)

Ref Expression
Hypotheses idlsrgmulrval.1 ⊢ S = IDLsrg ⁡ R
idlsrgmulrval.2 ⊢ B = LIdeal ⁡ R
idlsrgmulrval.3 ⊢ ⊗ ˙ = ⋅ S
idlsrgmulrval.4 ⊢ G = mulGrp R
idlsrgmulrval.5 ⊢ · ˙ = LSSum ⁡ G
idlsrgmulrval.6 ⊢ φ → R ∈ V
idlsrgmulrval.7 ⊢ φ → I ∈ B
idlsrgmulrval.8 ⊢ φ → J ∈ B
Assertion idlsrgmulrval ⊢ φ → I ⊗ ˙ J = RSpan ⁡ R ⁡ I · ˙ J

Proof

Step Hyp Ref Expression
1 idlsrgmulrval.1 ⊢ S = IDLsrg ⁡ R
2 idlsrgmulrval.2 ⊢ B = LIdeal ⁡ R
3 idlsrgmulrval.3 ⊢ ⊗ ˙ = ⋅ S
4 idlsrgmulrval.4 ⊢ G = mulGrp R
5 idlsrgmulrval.5 ⊢ · ˙ = LSSum ⁡ G
6 idlsrgmulrval.6 ⊢ φ → R ∈ V
7 idlsrgmulrval.7 ⊢ φ → I ∈ B
8 idlsrgmulrval.8 ⊢ φ → J ∈ B
9 1 2 4 5 idlsrgmulr ⊢ R ∈ V → x ∈ B , y ∈ B ⟼ RSpan ⁡ R ⁡ x · ˙ y = ⋅ S
10 6 9 syl ⊢ φ → x ∈ B , y ∈ B ⟼ RSpan ⁡ R ⁡ x · ˙ y = ⋅ S
11 3 10 eqtr4id ⊢ φ → ⊗ ˙ = x ∈ B , y ∈ B ⟼ RSpan ⁡ R ⁡ x · ˙ y
12 oveq12 ⊢ x = I ∧ y = J → x · ˙ y = I · ˙ J
13 12 adantl ⊢ φ ∧ x = I ∧ y = J → x · ˙ y = I · ˙ J
14 13 fveq2d ⊢ φ ∧ x = I ∧ y = J → RSpan ⁡ R ⁡ x · ˙ y = RSpan ⁡ R ⁡ I · ˙ J
15 fvexd ⊢ φ → RSpan ⁡ R ⁡ I · ˙ J ∈ V
16 11 14 7 8 15 ovmpod ⊢ φ → I ⊗ ˙ J = RSpan ⁡ R ⁡ I · ˙ J