| Step | Hyp | Ref
| Expression |
| 1 | | elaltxp 35917 |
. . 3
⊢ (𝑧 ∈ (𝐴 ×× 𝐵) ↔ ∃𝑥 ∈ 𝐴 ∃𝑦 ∈ 𝐵 𝑧 = ⟪𝑥, 𝑦⟫) |
| 2 | | df-altop 35900 |
. . . . . 6
⊢
⟪𝑥, 𝑦⟫ = {{𝑥}, {𝑥, {𝑦}}} |
| 3 | | snssi 4790 |
. . . . . . . . 9
⊢ (𝑥 ∈ 𝐴 → {𝑥} ⊆ 𝐴) |
| 4 | | ssun3 4162 |
. . . . . . . . 9
⊢ ({𝑥} ⊆ 𝐴 → {𝑥} ⊆ (𝐴 ∪ 𝒫 𝐵)) |
| 5 | 3, 4 | syl 17 |
. . . . . . . 8
⊢ (𝑥 ∈ 𝐴 → {𝑥} ⊆ (𝐴 ∪ 𝒫 𝐵)) |
| 6 | 5 | adantr 480 |
. . . . . . 7
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → {𝑥} ⊆ (𝐴 ∪ 𝒫 𝐵)) |
| 7 | | elun1 4164 |
. . . . . . . . 9
⊢ (𝑥 ∈ 𝐴 → 𝑥 ∈ (𝐴 ∪ 𝒫 𝐵)) |
| 8 | | snssi 4790 |
. . . . . . . . . 10
⊢ (𝑦 ∈ 𝐵 → {𝑦} ⊆ 𝐵) |
| 9 | | vsnex 5416 |
. . . . . . . . . . . 12
⊢ {𝑦} ∈ V |
| 10 | 9 | elpw 4586 |
. . . . . . . . . . 11
⊢ ({𝑦} ∈ 𝒫 𝐵 ↔ {𝑦} ⊆ 𝐵) |
| 11 | | elun2 4165 |
. . . . . . . . . . 11
⊢ ({𝑦} ∈ 𝒫 𝐵 → {𝑦} ∈ (𝐴 ∪ 𝒫 𝐵)) |
| 12 | 10, 11 | sylbir 235 |
. . . . . . . . . 10
⊢ ({𝑦} ⊆ 𝐵 → {𝑦} ∈ (𝐴 ∪ 𝒫 𝐵)) |
| 13 | 8, 12 | syl 17 |
. . . . . . . . 9
⊢ (𝑦 ∈ 𝐵 → {𝑦} ∈ (𝐴 ∪ 𝒫 𝐵)) |
| 14 | 7, 13 | anim12i 613 |
. . . . . . . 8
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → (𝑥 ∈ (𝐴 ∪ 𝒫 𝐵) ∧ {𝑦} ∈ (𝐴 ∪ 𝒫 𝐵))) |
| 15 | | vex 3468 |
. . . . . . . . 9
⊢ 𝑥 ∈ V |
| 16 | 15, 9 | prss 4802 |
. . . . . . . 8
⊢ ((𝑥 ∈ (𝐴 ∪ 𝒫 𝐵) ∧ {𝑦} ∈ (𝐴 ∪ 𝒫 𝐵)) ↔ {𝑥, {𝑦}} ⊆ (𝐴 ∪ 𝒫 𝐵)) |
| 17 | 14, 16 | sylib 218 |
. . . . . . 7
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → {𝑥, {𝑦}} ⊆ (𝐴 ∪ 𝒫 𝐵)) |
| 18 | | prex 5419 |
. . . . . . . . 9
⊢ {{𝑥}, {𝑥, {𝑦}}} ∈ V |
| 19 | 18 | elpw 4586 |
. . . . . . . 8
⊢ ({{𝑥}, {𝑥, {𝑦}}} ∈ 𝒫 𝒫 (𝐴 ∪ 𝒫 𝐵) ↔ {{𝑥}, {𝑥, {𝑦}}} ⊆ 𝒫 (𝐴 ∪ 𝒫 𝐵)) |
| 20 | | vsnex 5416 |
. . . . . . . . 9
⊢ {𝑥} ∈ V |
| 21 | | prex 5419 |
. . . . . . . . 9
⊢ {𝑥, {𝑦}} ∈ V |
| 22 | 20, 21 | prsspw 4827 |
. . . . . . . 8
⊢ ({{𝑥}, {𝑥, {𝑦}}} ⊆ 𝒫 (𝐴 ∪ 𝒫 𝐵) ↔ ({𝑥} ⊆ (𝐴 ∪ 𝒫 𝐵) ∧ {𝑥, {𝑦}} ⊆ (𝐴 ∪ 𝒫 𝐵))) |
| 23 | 19, 22 | bitri 275 |
. . . . . . 7
⊢ ({{𝑥}, {𝑥, {𝑦}}} ∈ 𝒫 𝒫 (𝐴 ∪ 𝒫 𝐵) ↔ ({𝑥} ⊆ (𝐴 ∪ 𝒫 𝐵) ∧ {𝑥, {𝑦}} ⊆ (𝐴 ∪ 𝒫 𝐵))) |
| 24 | 6, 17, 23 | sylanbrc 583 |
. . . . . 6
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → {{𝑥}, {𝑥, {𝑦}}} ∈ 𝒫 𝒫 (𝐴 ∪ 𝒫 𝐵)) |
| 25 | 2, 24 | eqeltrid 2837 |
. . . . 5
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → ⟪𝑥, 𝑦⟫ ∈ 𝒫 𝒫 (𝐴 ∪ 𝒫 𝐵)) |
| 26 | | eleq1a 2828 |
. . . . 5
⊢
(⟪𝑥, 𝑦⟫ ∈ 𝒫
𝒫 (𝐴 ∪
𝒫 𝐵) → (𝑧 = ⟪𝑥, 𝑦⟫ → 𝑧 ∈ 𝒫 𝒫 (𝐴 ∪ 𝒫 𝐵))) |
| 27 | 25, 26 | syl 17 |
. . . 4
⊢ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) → (𝑧 = ⟪𝑥, 𝑦⟫ → 𝑧 ∈ 𝒫 𝒫 (𝐴 ∪ 𝒫 𝐵))) |
| 28 | 27 | rexlimivv 3188 |
. . 3
⊢
(∃𝑥 ∈
𝐴 ∃𝑦 ∈ 𝐵 𝑧 = ⟪𝑥, 𝑦⟫ → 𝑧 ∈ 𝒫 𝒫 (𝐴 ∪ 𝒫 𝐵)) |
| 29 | 1, 28 | sylbi 217 |
. 2
⊢ (𝑧 ∈ (𝐴 ×× 𝐵) → 𝑧 ∈ 𝒫 𝒫 (𝐴 ∪ 𝒫 𝐵)) |
| 30 | 29 | ssriv 3969 |
1
⊢ (𝐴 ×× 𝐵) ⊆ 𝒫 𝒫
(𝐴 ∪ 𝒫 𝐵) |