| Step | Hyp | Ref
| Expression |
| 1 | | elxpi 4679 |
. . . 4
⊢ (𝑧 ∈ (𝐴 × 𝐵) → ∃𝑥∃𝑦(𝑧 = 〈𝑥, 𝑦〉 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵))) |
| 2 | | vex 2766 |
. . . . . . . 8
⊢ 𝑥 ∈ V |
| 3 | | vex 2766 |
. . . . . . . 8
⊢ 𝑦 ∈ V |
| 4 | 2, 3 | dfop 3807 |
. . . . . . 7
⊢
〈𝑥, 𝑦〉 = {{𝑥}, {𝑥, 𝑦}} |
| 5 | | snssi 3766 |
. . . . . . . . . . . . 13
⊢ (𝑥 ∈ 𝐴 → {𝑥} ⊆ 𝐴) |
| 6 | | ssun3 3328 |
. . . . . . . . . . . . 13
⊢ ({𝑥} ⊆ 𝐴 → {𝑥} ⊆ (𝐴 ∪ 𝐵)) |
| 7 | 5, 6 | syl 14 |
. . . . . . . . . . . 12
⊢ (𝑥 ∈ 𝐴 → {𝑥} ⊆ (𝐴 ∪ 𝐵)) |
| 8 | 7 | adantr 276 |
. . . . . . . . . . 11
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → {𝑥} ⊆ (𝐴 ∪ 𝐵)) |
| 9 | | sseq1 3206 |
. . . . . . . . . . 11
⊢ (𝑧 = {𝑥} → (𝑧 ⊆ (𝐴 ∪ 𝐵) ↔ {𝑥} ⊆ (𝐴 ∪ 𝐵))) |
| 10 | 8, 9 | syl5ibrcom 157 |
. . . . . . . . . 10
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → (𝑧 = {𝑥} → 𝑧 ⊆ (𝐴 ∪ 𝐵))) |
| 11 | | df-pr 3629 |
. . . . . . . . . . . 12
⊢ {𝑥, 𝑦} = ({𝑥} ∪ {𝑦}) |
| 12 | | snssi 3766 |
. . . . . . . . . . . . . . 15
⊢ (𝑦 ∈ 𝐵 → {𝑦} ⊆ 𝐵) |
| 13 | | ssun4 3329 |
. . . . . . . . . . . . . . 15
⊢ ({𝑦} ⊆ 𝐵 → {𝑦} ⊆ (𝐴 ∪ 𝐵)) |
| 14 | 12, 13 | syl 14 |
. . . . . . . . . . . . . 14
⊢ (𝑦 ∈ 𝐵 → {𝑦} ⊆ (𝐴 ∪ 𝐵)) |
| 15 | 7, 14 | anim12i 338 |
. . . . . . . . . . . . 13
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → ({𝑥} ⊆ (𝐴 ∪ 𝐵) ∧ {𝑦} ⊆ (𝐴 ∪ 𝐵))) |
| 16 | | unss 3337 |
. . . . . . . . . . . . 13
⊢ (({𝑥} ⊆ (𝐴 ∪ 𝐵) ∧ {𝑦} ⊆ (𝐴 ∪ 𝐵)) ↔ ({𝑥} ∪ {𝑦}) ⊆ (𝐴 ∪ 𝐵)) |
| 17 | 15, 16 | sylib 122 |
. . . . . . . . . . . 12
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → ({𝑥} ∪ {𝑦}) ⊆ (𝐴 ∪ 𝐵)) |
| 18 | 11, 17 | eqsstrid 3229 |
. . . . . . . . . . 11
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → {𝑥, 𝑦} ⊆ (𝐴 ∪ 𝐵)) |
| 19 | | sseq1 3206 |
. . . . . . . . . . 11
⊢ (𝑧 = {𝑥, 𝑦} → (𝑧 ⊆ (𝐴 ∪ 𝐵) ↔ {𝑥, 𝑦} ⊆ (𝐴 ∪ 𝐵))) |
| 20 | 18, 19 | syl5ibrcom 157 |
. . . . . . . . . 10
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → (𝑧 = {𝑥, 𝑦} → 𝑧 ⊆ (𝐴 ∪ 𝐵))) |
| 21 | 10, 20 | jaod 718 |
. . . . . . . . 9
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → ((𝑧 = {𝑥} ∨ 𝑧 = {𝑥, 𝑦}) → 𝑧 ⊆ (𝐴 ∪ 𝐵))) |
| 22 | | vex 2766 |
. . . . . . . . . 10
⊢ 𝑧 ∈ V |
| 23 | 22 | elpr 3643 |
. . . . . . . . 9
⊢ (𝑧 ∈ {{𝑥}, {𝑥, 𝑦}} ↔ (𝑧 = {𝑥} ∨ 𝑧 = {𝑥, 𝑦})) |
| 24 | 22 | elpw 3611 |
. . . . . . . . 9
⊢ (𝑧 ∈ 𝒫 (𝐴 ∪ 𝐵) ↔ 𝑧 ⊆ (𝐴 ∪ 𝐵)) |
| 25 | 21, 23, 24 | 3imtr4g 205 |
. . . . . . . 8
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → (𝑧 ∈ {{𝑥}, {𝑥, 𝑦}} → 𝑧 ∈ 𝒫 (𝐴 ∪ 𝐵))) |
| 26 | 25 | ssrdv 3189 |
. . . . . . 7
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → {{𝑥}, {𝑥, 𝑦}} ⊆ 𝒫 (𝐴 ∪ 𝐵)) |
| 27 | 4, 26 | eqsstrid 3229 |
. . . . . 6
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → 〈𝑥, 𝑦〉 ⊆ 𝒫 (𝐴 ∪ 𝐵)) |
| 28 | | sseq1 3206 |
. . . . . . 7
⊢ (𝑧 = 〈𝑥, 𝑦〉 → (𝑧 ⊆ 𝒫 (𝐴 ∪ 𝐵) ↔ 〈𝑥, 𝑦〉 ⊆ 𝒫 (𝐴 ∪ 𝐵))) |
| 29 | 28 | biimpar 297 |
. . . . . 6
⊢ ((𝑧 = 〈𝑥, 𝑦〉 ∧ 〈𝑥, 𝑦〉 ⊆ 𝒫 (𝐴 ∪ 𝐵)) → 𝑧 ⊆ 𝒫 (𝐴 ∪ 𝐵)) |
| 30 | 27, 29 | sylan2 286 |
. . . . 5
⊢ ((𝑧 = 〈𝑥, 𝑦〉 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → 𝑧 ⊆ 𝒫 (𝐴 ∪ 𝐵)) |
| 31 | 30 | exlimivv 1911 |
. . . 4
⊢
(∃𝑥∃𝑦(𝑧 = 〈𝑥, 𝑦〉 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → 𝑧 ⊆ 𝒫 (𝐴 ∪ 𝐵)) |
| 32 | 1, 31 | syl 14 |
. . 3
⊢ (𝑧 ∈ (𝐴 × 𝐵) → 𝑧 ⊆ 𝒫 (𝐴 ∪ 𝐵)) |
| 33 | 22 | elpw 3611 |
. . 3
⊢ (𝑧 ∈ 𝒫 𝒫
(𝐴 ∪ 𝐵) ↔ 𝑧 ⊆ 𝒫 (𝐴 ∪ 𝐵)) |
| 34 | 32, 33 | sylibr 134 |
. 2
⊢ (𝑧 ∈ (𝐴 × 𝐵) → 𝑧 ∈ 𝒫 𝒫 (𝐴 ∪ 𝐵)) |
| 35 | 34 | ssriv 3187 |
1
⊢ (𝐴 × 𝐵) ⊆ 𝒫 𝒫 (𝐴 ∪ 𝐵) |