| Step | Hyp | Ref
| Expression |
| 1 | | nfv 1619 |
. . . . 5
⊢ Ⅎz x ∈ A |
| 2 | | cbvmpt2x.1 |
. . . . . 6
⊢
ℲzB |
| 3 | 2 | nfcri 2484 |
. . . . 5
⊢ Ⅎz y ∈ B |
| 4 | 1, 3 | nfan 1824 |
. . . 4
⊢ Ⅎz(x ∈ A ∧ y ∈ B) |
| 5 | | cbvmpt2x.3 |
. . . . 5
⊢
ℲzC |
| 6 | 5 | nfeq2 2501 |
. . . 4
⊢ Ⅎz u = C |
| 7 | 4, 6 | nfan 1824 |
. . 3
⊢ Ⅎz((x ∈ A ∧ y ∈ B) ∧ u = C) |
| 8 | | nfv 1619 |
. . . . 5
⊢ Ⅎw x ∈ A |
| 9 | | nfcv 2490 |
. . . . . 6
⊢
ℲwB |
| 10 | 9 | nfcri 2484 |
. . . . 5
⊢ Ⅎw y ∈ B |
| 11 | 8, 10 | nfan 1824 |
. . . 4
⊢ Ⅎw(x ∈ A ∧ y ∈ B) |
| 12 | | cbvmpt2x.4 |
. . . . 5
⊢
ℲwC |
| 13 | 12 | nfeq2 2501 |
. . . 4
⊢ Ⅎw u = C |
| 14 | 11, 13 | nfan 1824 |
. . 3
⊢ Ⅎw((x ∈ A ∧ y ∈ B) ∧ u = C) |
| 15 | | nfv 1619 |
. . . . 5
⊢ Ⅎx z ∈ A |
| 16 | | cbvmpt2x.2 |
. . . . . 6
⊢
ℲxD |
| 17 | 16 | nfcri 2484 |
. . . . 5
⊢ Ⅎx w ∈ D |
| 18 | 15, 17 | nfan 1824 |
. . . 4
⊢ Ⅎx(z ∈ A ∧ w ∈ D) |
| 19 | | cbvmpt2x.5 |
. . . . 5
⊢
ℲxE |
| 20 | 19 | nfeq2 2501 |
. . . 4
⊢ Ⅎx u = E |
| 21 | 18, 20 | nfan 1824 |
. . 3
⊢ Ⅎx((z ∈ A ∧ w ∈ D) ∧ u = E) |
| 22 | | nfv 1619 |
. . . 4
⊢ Ⅎy(z ∈ A ∧ w ∈ D) |
| 23 | | cbvmpt2x.6 |
. . . . 5
⊢
ℲyE |
| 24 | 23 | nfeq2 2501 |
. . . 4
⊢ Ⅎy u = E |
| 25 | 22, 24 | nfan 1824 |
. . 3
⊢ Ⅎy((z ∈ A ∧ w ∈ D) ∧ u = E) |
| 26 | | eleq1 2413 |
. . . . . 6
⊢ (x = z →
(x ∈
A ↔ z ∈ A)) |
| 27 | 26 | adantr 451 |
. . . . 5
⊢ ((x = z ∧ y = w) → (x
∈ A
↔ z ∈ A)) |
| 28 | | cbvmpt2x.7 |
. . . . . . 7
⊢ (x = z →
B = D) |
| 29 | 28 | eleq2d 2420 |
. . . . . 6
⊢ (x = z →
(y ∈
B ↔ y ∈ D)) |
| 30 | | eleq1 2413 |
. . . . . 6
⊢ (y = w →
(y ∈
D ↔ w ∈ D)) |
| 31 | 29, 30 | sylan9bb 680 |
. . . . 5
⊢ ((x = z ∧ y = w) → (y
∈ B
↔ w ∈ D)) |
| 32 | 27, 31 | anbi12d 691 |
. . . 4
⊢ ((x = z ∧ y = w) → ((x
∈ A ∧ y ∈ B) ↔
(z ∈
A ∧
w ∈
D))) |
| 33 | | cbvmpt2x.8 |
. . . . 5
⊢ ((x = z ∧ y = w) → C =
E) |
| 34 | 33 | eqeq2d 2364 |
. . . 4
⊢ ((x = z ∧ y = w) → (u =
C ↔ u = E)) |
| 35 | 32, 34 | anbi12d 691 |
. . 3
⊢ ((x = z ∧ y = w) → (((x
∈ A ∧ y ∈ B) ∧ u = C) ↔ ((z
∈ A ∧ w ∈ D) ∧ u = E))) |
| 36 | 7, 14, 21, 25, 35 | cbvoprab12 5570 |
. 2
⊢ {〈〈x, y〉, u〉 ∣ ((x ∈ A ∧ y ∈ B) ∧ u = C)} = {〈〈z, w〉, u〉 ∣ ((z ∈ A ∧ w ∈ D) ∧ u = E)} |
| 37 | | df-mpt2 5655 |
. 2
⊢ (x ∈ A, y ∈ B ↦ C) = {〈〈x, y〉, u〉 ∣ ((x ∈ A ∧ y ∈ B) ∧ u = C)} |
| 38 | | df-mpt2 5655 |
. 2
⊢ (z ∈ A, w ∈ D ↦ E) = {〈〈z, w〉, u〉 ∣ ((z ∈ A ∧ w ∈ D) ∧ u = E)} |
| 39 | 36, 37, 38 | 3eqtr4i 2383 |
1
⊢ (x ∈ A, y ∈ B ↦ C) =
(z ∈
A, w
∈ D ↦ E) |