Proof of Theorem eroprf
| Step | Hyp | Ref
 | Expression | 
| 1 |   | eropr.3 | 
. . . . . . . . . . . 12
⊢ (𝜑 → 𝑇 ∈ 𝑍) | 
| 2 | 1 | ad2antrr 488 | 
. . . . . . . . . . 11
⊢ (((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) ∧ (𝑝 ∈ 𝐴 ∧ 𝑞 ∈ 𝐵)) → 𝑇 ∈ 𝑍) | 
| 3 |   | eropr.10 | 
. . . . . . . . . . . . 13
⊢ (𝜑 → + :(𝐴 × 𝐵)⟶𝐶) | 
| 4 | 3 | adantr 276 | 
. . . . . . . . . . . 12
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) → + :(𝐴 × 𝐵)⟶𝐶) | 
| 5 | 4 | fovcdmda 6067 | 
. . . . . . . . . . 11
⊢ (((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) ∧ (𝑝 ∈ 𝐴 ∧ 𝑞 ∈ 𝐵)) → (𝑝 + 𝑞) ∈ 𝐶) | 
| 6 |   | ecelqsg 6647 | 
. . . . . . . . . . 11
⊢ ((𝑇 ∈ 𝑍 ∧ (𝑝 + 𝑞) ∈ 𝐶) → [(𝑝 + 𝑞)]𝑇 ∈ (𝐶 / 𝑇)) | 
| 7 | 2, 5, 6 | syl2anc 411 | 
. . . . . . . . . 10
⊢ (((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) ∧ (𝑝 ∈ 𝐴 ∧ 𝑞 ∈ 𝐵)) → [(𝑝 + 𝑞)]𝑇 ∈ (𝐶 / 𝑇)) | 
| 8 |   | eropr.15 | 
. . . . . . . . . 10
⊢ 𝐿 = (𝐶 / 𝑇) | 
| 9 | 7, 8 | eleqtrrdi 2290 | 
. . . . . . . . 9
⊢ (((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) ∧ (𝑝 ∈ 𝐴 ∧ 𝑞 ∈ 𝐵)) → [(𝑝 + 𝑞)]𝑇 ∈ 𝐿) | 
| 10 |   | eleq1a 2268 | 
. . . . . . . . 9
⊢ ([(𝑝 + 𝑞)]𝑇 ∈ 𝐿 → (𝑧 = [(𝑝 + 𝑞)]𝑇 → 𝑧 ∈ 𝐿)) | 
| 11 | 9, 10 | syl 14 | 
. . . . . . . 8
⊢ (((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) ∧ (𝑝 ∈ 𝐴 ∧ 𝑞 ∈ 𝐵)) → (𝑧 = [(𝑝 + 𝑞)]𝑇 → 𝑧 ∈ 𝐿)) | 
| 12 | 11 | adantld 278 | 
. . . . . . 7
⊢ (((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) ∧ (𝑝 ∈ 𝐴 ∧ 𝑞 ∈ 𝐵)) → (((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇) → 𝑧 ∈ 𝐿)) | 
| 13 | 12 | rexlimdvva 2622 | 
. . . . . 6
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) → (∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇) → 𝑧 ∈ 𝐿)) | 
| 14 | 13 | abssdv 3257 | 
. . . . 5
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) → {𝑧 ∣ ∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)} ⊆ 𝐿) | 
| 15 |   | eropr.1 | 
. . . . . . 7
⊢ 𝐽 = (𝐴 / 𝑅) | 
| 16 |   | eropr.2 | 
. . . . . . 7
⊢ 𝐾 = (𝐵 / 𝑆) | 
| 17 |   | eropr.4 | 
. . . . . . 7
⊢ (𝜑 → 𝑅 Er 𝑈) | 
| 18 |   | eropr.5 | 
. . . . . . 7
⊢ (𝜑 → 𝑆 Er 𝑉) | 
| 19 |   | eropr.6 | 
. . . . . . 7
⊢ (𝜑 → 𝑇 Er 𝑊) | 
| 20 |   | eropr.7 | 
. . . . . . 7
⊢ (𝜑 → 𝐴 ⊆ 𝑈) | 
| 21 |   | eropr.8 | 
. . . . . . 7
⊢ (𝜑 → 𝐵 ⊆ 𝑉) | 
| 22 |   | eropr.9 | 
. . . . . . 7
⊢ (𝜑 → 𝐶 ⊆ 𝑊) | 
| 23 |   | eropr.11 | 
. . . . . . 7
⊢ ((𝜑 ∧ ((𝑟 ∈ 𝐴 ∧ 𝑠 ∈ 𝐴) ∧ (𝑡 ∈ 𝐵 ∧ 𝑢 ∈ 𝐵))) → ((𝑟𝑅𝑠 ∧ 𝑡𝑆𝑢) → (𝑟 + 𝑡)𝑇(𝑠 + 𝑢))) | 
| 24 | 15, 16, 1, 17, 18, 19, 20, 21, 22, 3, 23 | eroveu 6685 | 
. . . . . 6
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) → ∃!𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)) | 
| 25 |   | iotacl 5243 | 
. . . . . 6
⊢
(∃!𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇) → (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)) ∈ {𝑧 ∣ ∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)}) | 
| 26 | 24, 25 | syl 14 | 
. . . . 5
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) → (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)) ∈ {𝑧 ∣ ∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)}) | 
| 27 | 14, 26 | sseldd 3184 | 
. . . 4
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐽 ∧ 𝑦 ∈ 𝐾)) → (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)) ∈ 𝐿) | 
| 28 | 27 | ralrimivva 2579 | 
. . 3
⊢ (𝜑 → ∀𝑥 ∈ 𝐽 ∀𝑦 ∈ 𝐾 (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)) ∈ 𝐿) | 
| 29 |   | eqid 2196 | 
. . . 4
⊢ (𝑥 ∈ 𝐽, 𝑦 ∈ 𝐾 ↦ (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇))) = (𝑥 ∈ 𝐽, 𝑦 ∈ 𝐾 ↦ (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇))) | 
| 30 | 29 | fmpo 6259 | 
. . 3
⊢
(∀𝑥 ∈
𝐽 ∀𝑦 ∈ 𝐾 (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)) ∈ 𝐿 ↔ (𝑥 ∈ 𝐽, 𝑦 ∈ 𝐾 ↦ (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇))):(𝐽 × 𝐾)⟶𝐿) | 
| 31 | 28, 30 | sylib 122 | 
. 2
⊢ (𝜑 → (𝑥 ∈ 𝐽, 𝑦 ∈ 𝐾 ↦ (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇))):(𝐽 × 𝐾)⟶𝐿) | 
| 32 |   | eropr.12 | 
. . . 4
⊢  ⨣ =
{〈〈𝑥, 𝑦〉, 𝑧〉 ∣ ∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)} | 
| 33 | 15, 16, 1, 17, 18, 19, 20, 21, 22, 3, 23, 32 | erovlem 6686 | 
. . 3
⊢ (𝜑 → ⨣ = (𝑥 ∈ 𝐽, 𝑦 ∈ 𝐾 ↦ (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇)))) | 
| 34 | 33 | feq1d 5394 | 
. 2
⊢ (𝜑 → ( ⨣ :(𝐽 × 𝐾)⟶𝐿 ↔ (𝑥 ∈ 𝐽, 𝑦 ∈ 𝐾 ↦ (℩𝑧∃𝑝 ∈ 𝐴 ∃𝑞 ∈ 𝐵 ((𝑥 = [𝑝]𝑅 ∧ 𝑦 = [𝑞]𝑆) ∧ 𝑧 = [(𝑝 + 𝑞)]𝑇))):(𝐽 × 𝐾)⟶𝐿)) | 
| 35 | 31, 34 | mpbird 167 | 
1
⊢ (𝜑 → ⨣ :(𝐽 × 𝐾)⟶𝐿) |