Proof of Theorem iinrab2
Step | Hyp | Ref
| Expression |
1 | | iineq1 3984 |
. . . . . 6
⊢ (A = ∅ →
∩x ∈ A {y ∈ B ∣ φ} = ∩x ∈ ∅ {y ∈ B ∣ φ}) |
2 | | 0iin 4025 |
. . . . . 6
⊢ ∩x ∈ ∅ {y ∈ B ∣ φ} = V |
3 | 1, 2 | syl6eq 2401 |
. . . . 5
⊢ (A = ∅ →
∩x ∈ A {y ∈ B ∣ φ} = V) |
4 | 3 | ineq1d 3457 |
. . . 4
⊢ (A = ∅ →
(∩x ∈ A {y ∈ B ∣ φ} ∩ B) = (V ∩ B)) |
5 | | incom 3449 |
. . . . 5
⊢ (V ∩ B) = (B ∩
V) |
6 | | inv1 3578 |
. . . . 5
⊢ (B ∩ V) = B |
7 | 5, 6 | eqtri 2373 |
. . . 4
⊢ (V ∩ B) = B |
8 | 4, 7 | syl6eq 2401 |
. . 3
⊢ (A = ∅ →
(∩x ∈ A {y ∈ B ∣ φ} ∩ B) = B) |
9 | | rzal 3652 |
. . . 4
⊢ (A = ∅ →
∀x
∈ A ∀y ∈ B φ) |
10 | | rabid2 2789 |
. . . . 5
⊢ (B = {y ∈ B ∣ ∀x ∈ A φ} ↔
∀y
∈ B ∀x ∈ A φ) |
11 | | ralcom 2772 |
. . . . 5
⊢ (∀y ∈ B ∀x ∈ A φ ↔ ∀x ∈ A ∀y ∈ B φ) |
12 | 10, 11 | bitr2i 241 |
. . . 4
⊢ (∀x ∈ A ∀y ∈ B φ ↔ B = {y ∈ B ∣ ∀x ∈ A φ}) |
13 | 9, 12 | sylib 188 |
. . 3
⊢ (A = ∅ →
B = {y
∈ B ∣ ∀x ∈ A φ}) |
14 | 8, 13 | eqtrd 2385 |
. 2
⊢ (A = ∅ →
(∩x ∈ A {y ∈ B ∣ φ} ∩ B) = {y ∈ B ∣ ∀x ∈ A φ}) |
15 | | iinrab 4029 |
. . . 4
⊢ (A ≠ ∅ →
∩x ∈ A {y ∈ B ∣ φ} = {y
∈ B ∣ ∀x ∈ A φ}) |
16 | 15 | ineq1d 3457 |
. . 3
⊢ (A ≠ ∅ →
(∩x ∈ A {y ∈ B ∣ φ} ∩ B) = ({y ∈ B ∣ ∀x ∈ A φ} ∩
B)) |
17 | | ssrab2 3352 |
. . . 4
⊢ {y ∈ B ∣ ∀x ∈ A φ} ⊆
B |
18 | | dfss 3261 |
. . . 4
⊢ ({y ∈ B ∣ ∀x ∈ A φ} ⊆
B ↔ {y ∈ B ∣ ∀x ∈ A φ} = ({y
∈ B ∣ ∀x ∈ A φ} ∩
B)) |
19 | 17, 18 | mpbi 199 |
. . 3
⊢ {y ∈ B ∣ ∀x ∈ A φ} = ({y
∈ B ∣ ∀x ∈ A φ} ∩
B) |
20 | 16, 19 | syl6eqr 2403 |
. 2
⊢ (A ≠ ∅ →
(∩x ∈ A {y ∈ B ∣ φ} ∩ B) = {y ∈ B ∣ ∀x ∈ A φ}) |
21 | 14, 20 | pm2.61ine 2593 |
1
⊢ (∩x ∈ A {y ∈ B ∣ φ} ∩ B) = {y ∈ B ∣ ∀x ∈ A φ} |