| Step | Hyp | Ref | Expression | 
|---|
| 1 |  | addsunif.1 | . . 3
⊢ (𝜑 → 𝐿 <<s 𝑅) | 
| 2 |  | addsunif.2 | . . 3
⊢ (𝜑 → 𝑀 <<s 𝑆) | 
| 3 |  | addsunif.3 | . . 3
⊢ (𝜑 → 𝐴 = (𝐿 |s 𝑅)) | 
| 4 |  | addsunif.4 | . . 3
⊢ (𝜑 → 𝐵 = (𝑀 |s 𝑆)) | 
| 5 | 1, 2, 3, 4 | addsuniflem 28034 | . 2
⊢ (𝜑 → (𝐴 +s 𝐵) = (({𝑎 ∣ ∃𝑏 ∈ 𝐿 𝑎 = (𝑏 +s 𝐵)} ∪ {𝑐 ∣ ∃𝑑 ∈ 𝑀 𝑐 = (𝐴 +s 𝑑)}) |s ({𝑒 ∣ ∃𝑓 ∈ 𝑅 𝑒 = (𝑓 +s 𝐵)} ∪ {𝑔 ∣ ∃ℎ ∈ 𝑆 𝑔 = (𝐴 +s ℎ)}))) | 
| 6 |  | oveq1 7438 | . . . . . . . 8
⊢ (𝑙 = 𝑏 → (𝑙 +s 𝐵) = (𝑏 +s 𝐵)) | 
| 7 | 6 | eqeq2d 2748 | . . . . . . 7
⊢ (𝑙 = 𝑏 → (𝑦 = (𝑙 +s 𝐵) ↔ 𝑦 = (𝑏 +s 𝐵))) | 
| 8 | 7 | cbvrexvw 3238 | . . . . . 6
⊢
(∃𝑙 ∈
𝐿 𝑦 = (𝑙 +s 𝐵) ↔ ∃𝑏 ∈ 𝐿 𝑦 = (𝑏 +s 𝐵)) | 
| 9 |  | eqeq1 2741 | . . . . . . 7
⊢ (𝑦 = 𝑎 → (𝑦 = (𝑏 +s 𝐵) ↔ 𝑎 = (𝑏 +s 𝐵))) | 
| 10 | 9 | rexbidv 3179 | . . . . . 6
⊢ (𝑦 = 𝑎 → (∃𝑏 ∈ 𝐿 𝑦 = (𝑏 +s 𝐵) ↔ ∃𝑏 ∈ 𝐿 𝑎 = (𝑏 +s 𝐵))) | 
| 11 | 8, 10 | bitrid 283 | . . . . 5
⊢ (𝑦 = 𝑎 → (∃𝑙 ∈ 𝐿 𝑦 = (𝑙 +s 𝐵) ↔ ∃𝑏 ∈ 𝐿 𝑎 = (𝑏 +s 𝐵))) | 
| 12 | 11 | cbvabv 2812 | . . . 4
⊢ {𝑦 ∣ ∃𝑙 ∈ 𝐿 𝑦 = (𝑙 +s 𝐵)} = {𝑎 ∣ ∃𝑏 ∈ 𝐿 𝑎 = (𝑏 +s 𝐵)} | 
| 13 |  | oveq2 7439 | . . . . . . . 8
⊢ (𝑚 = 𝑑 → (𝐴 +s 𝑚) = (𝐴 +s 𝑑)) | 
| 14 | 13 | eqeq2d 2748 | . . . . . . 7
⊢ (𝑚 = 𝑑 → (𝑧 = (𝐴 +s 𝑚) ↔ 𝑧 = (𝐴 +s 𝑑))) | 
| 15 | 14 | cbvrexvw 3238 | . . . . . 6
⊢
(∃𝑚 ∈
𝑀 𝑧 = (𝐴 +s 𝑚) ↔ ∃𝑑 ∈ 𝑀 𝑧 = (𝐴 +s 𝑑)) | 
| 16 |  | eqeq1 2741 | . . . . . . 7
⊢ (𝑧 = 𝑐 → (𝑧 = (𝐴 +s 𝑑) ↔ 𝑐 = (𝐴 +s 𝑑))) | 
| 17 | 16 | rexbidv 3179 | . . . . . 6
⊢ (𝑧 = 𝑐 → (∃𝑑 ∈ 𝑀 𝑧 = (𝐴 +s 𝑑) ↔ ∃𝑑 ∈ 𝑀 𝑐 = (𝐴 +s 𝑑))) | 
| 18 | 15, 17 | bitrid 283 | . . . . 5
⊢ (𝑧 = 𝑐 → (∃𝑚 ∈ 𝑀 𝑧 = (𝐴 +s 𝑚) ↔ ∃𝑑 ∈ 𝑀 𝑐 = (𝐴 +s 𝑑))) | 
| 19 | 18 | cbvabv 2812 | . . . 4
⊢ {𝑧 ∣ ∃𝑚 ∈ 𝑀 𝑧 = (𝐴 +s 𝑚)} = {𝑐 ∣ ∃𝑑 ∈ 𝑀 𝑐 = (𝐴 +s 𝑑)} | 
| 20 | 12, 19 | uneq12i 4166 | . . 3
⊢ ({𝑦 ∣ ∃𝑙 ∈ 𝐿 𝑦 = (𝑙 +s 𝐵)} ∪ {𝑧 ∣ ∃𝑚 ∈ 𝑀 𝑧 = (𝐴 +s 𝑚)}) = ({𝑎 ∣ ∃𝑏 ∈ 𝐿 𝑎 = (𝑏 +s 𝐵)} ∪ {𝑐 ∣ ∃𝑑 ∈ 𝑀 𝑐 = (𝐴 +s 𝑑)}) | 
| 21 |  | oveq1 7438 | . . . . . . . 8
⊢ (𝑟 = 𝑓 → (𝑟 +s 𝐵) = (𝑓 +s 𝐵)) | 
| 22 | 21 | eqeq2d 2748 | . . . . . . 7
⊢ (𝑟 = 𝑓 → (𝑤 = (𝑟 +s 𝐵) ↔ 𝑤 = (𝑓 +s 𝐵))) | 
| 23 | 22 | cbvrexvw 3238 | . . . . . 6
⊢
(∃𝑟 ∈
𝑅 𝑤 = (𝑟 +s 𝐵) ↔ ∃𝑓 ∈ 𝑅 𝑤 = (𝑓 +s 𝐵)) | 
| 24 |  | eqeq1 2741 | . . . . . . 7
⊢ (𝑤 = 𝑒 → (𝑤 = (𝑓 +s 𝐵) ↔ 𝑒 = (𝑓 +s 𝐵))) | 
| 25 | 24 | rexbidv 3179 | . . . . . 6
⊢ (𝑤 = 𝑒 → (∃𝑓 ∈ 𝑅 𝑤 = (𝑓 +s 𝐵) ↔ ∃𝑓 ∈ 𝑅 𝑒 = (𝑓 +s 𝐵))) | 
| 26 | 23, 25 | bitrid 283 | . . . . 5
⊢ (𝑤 = 𝑒 → (∃𝑟 ∈ 𝑅 𝑤 = (𝑟 +s 𝐵) ↔ ∃𝑓 ∈ 𝑅 𝑒 = (𝑓 +s 𝐵))) | 
| 27 | 26 | cbvabv 2812 | . . . 4
⊢ {𝑤 ∣ ∃𝑟 ∈ 𝑅 𝑤 = (𝑟 +s 𝐵)} = {𝑒 ∣ ∃𝑓 ∈ 𝑅 𝑒 = (𝑓 +s 𝐵)} | 
| 28 |  | oveq2 7439 | . . . . . . . 8
⊢ (𝑠 = ℎ → (𝐴 +s 𝑠) = (𝐴 +s ℎ)) | 
| 29 | 28 | eqeq2d 2748 | . . . . . . 7
⊢ (𝑠 = ℎ → (𝑡 = (𝐴 +s 𝑠) ↔ 𝑡 = (𝐴 +s ℎ))) | 
| 30 | 29 | cbvrexvw 3238 | . . . . . 6
⊢
(∃𝑠 ∈
𝑆 𝑡 = (𝐴 +s 𝑠) ↔ ∃ℎ ∈ 𝑆 𝑡 = (𝐴 +s ℎ)) | 
| 31 |  | eqeq1 2741 | . . . . . . 7
⊢ (𝑡 = 𝑔 → (𝑡 = (𝐴 +s ℎ) ↔ 𝑔 = (𝐴 +s ℎ))) | 
| 32 | 31 | rexbidv 3179 | . . . . . 6
⊢ (𝑡 = 𝑔 → (∃ℎ ∈ 𝑆 𝑡 = (𝐴 +s ℎ) ↔ ∃ℎ ∈ 𝑆 𝑔 = (𝐴 +s ℎ))) | 
| 33 | 30, 32 | bitrid 283 | . . . . 5
⊢ (𝑡 = 𝑔 → (∃𝑠 ∈ 𝑆 𝑡 = (𝐴 +s 𝑠) ↔ ∃ℎ ∈ 𝑆 𝑔 = (𝐴 +s ℎ))) | 
| 34 | 33 | cbvabv 2812 | . . . 4
⊢ {𝑡 ∣ ∃𝑠 ∈ 𝑆 𝑡 = (𝐴 +s 𝑠)} = {𝑔 ∣ ∃ℎ ∈ 𝑆 𝑔 = (𝐴 +s ℎ)} | 
| 35 | 27, 34 | uneq12i 4166 | . . 3
⊢ ({𝑤 ∣ ∃𝑟 ∈ 𝑅 𝑤 = (𝑟 +s 𝐵)} ∪ {𝑡 ∣ ∃𝑠 ∈ 𝑆 𝑡 = (𝐴 +s 𝑠)}) = ({𝑒 ∣ ∃𝑓 ∈ 𝑅 𝑒 = (𝑓 +s 𝐵)} ∪ {𝑔 ∣ ∃ℎ ∈ 𝑆 𝑔 = (𝐴 +s ℎ)}) | 
| 36 | 20, 35 | oveq12i 7443 | . 2
⊢ (({𝑦 ∣ ∃𝑙 ∈ 𝐿 𝑦 = (𝑙 +s 𝐵)} ∪ {𝑧 ∣ ∃𝑚 ∈ 𝑀 𝑧 = (𝐴 +s 𝑚)}) |s ({𝑤 ∣ ∃𝑟 ∈ 𝑅 𝑤 = (𝑟 +s 𝐵)} ∪ {𝑡 ∣ ∃𝑠 ∈ 𝑆 𝑡 = (𝐴 +s 𝑠)})) = (({𝑎 ∣ ∃𝑏 ∈ 𝐿 𝑎 = (𝑏 +s 𝐵)} ∪ {𝑐 ∣ ∃𝑑 ∈ 𝑀 𝑐 = (𝐴 +s 𝑑)}) |s ({𝑒 ∣ ∃𝑓 ∈ 𝑅 𝑒 = (𝑓 +s 𝐵)} ∪ {𝑔 ∣ ∃ℎ ∈ 𝑆 𝑔 = (𝐴 +s ℎ)})) | 
| 37 | 5, 36 | eqtr4di 2795 | 1
⊢ (𝜑 → (𝐴 +s 𝐵) = (({𝑦 ∣ ∃𝑙 ∈ 𝐿 𝑦 = (𝑙 +s 𝐵)} ∪ {𝑧 ∣ ∃𝑚 ∈ 𝑀 𝑧 = (𝐴 +s 𝑚)}) |s ({𝑤 ∣ ∃𝑟 ∈ 𝑅 𝑤 = (𝑟 +s 𝐵)} ∪ {𝑡 ∣ ∃𝑠 ∈ 𝑆 𝑡 = (𝐴 +s 𝑠)}))) |