Proof of Theorem eldisjlem19
Step | Hyp | Ref
| Expression |
1 | | df-eldisj 38663 |
. . . . . . . 8
⊢ ( ElDisj
𝐴 ↔ Disj (◡ E ↾ 𝐴)) |
2 | | disjlem19 38757 |
. . . . . . . 8
⊢ (𝐵 ∈ 𝑉 → ( Disj (◡ E ↾ 𝐴) → ((𝑢 ∈ dom (◡ E ↾ 𝐴) ∧ 𝐵 ∈ [𝑢](◡ E
↾ 𝐴)) → [𝑢](◡ E ↾ 𝐴) = [𝐵] ≀ (◡ E ↾ 𝐴)))) |
3 | 1, 2 | biimtrid 242 |
. . . . . . 7
⊢ (𝐵 ∈ 𝑉 → ( ElDisj 𝐴 → ((𝑢 ∈ dom (◡ E ↾ 𝐴) ∧ 𝐵 ∈ [𝑢](◡ E
↾ 𝐴)) → [𝑢](◡ E ↾ 𝐴) = [𝐵] ≀ (◡ E ↾ 𝐴)))) |
4 | 3 | imp 406 |
. . . . . 6
⊢ ((𝐵 ∈ 𝑉 ∧ ElDisj 𝐴) → ((𝑢 ∈ dom (◡ E ↾ 𝐴) ∧ 𝐵 ∈ [𝑢](◡ E
↾ 𝐴)) → [𝑢](◡ E ↾ 𝐴) = [𝐵] ≀ (◡ E ↾ 𝐴))) |
5 | 4 | expdimp 452 |
. . . . 5
⊢ (((𝐵 ∈ 𝑉 ∧ ElDisj 𝐴) ∧ 𝑢 ∈ dom (◡ E ↾ 𝐴)) → (𝐵 ∈ [𝑢](◡ E
↾ 𝐴) → [𝑢](◡ E ↾ 𝐴) = [𝐵] ≀ (◡ E ↾ 𝐴))) |
6 | | eccnvepres3 38242 |
. . . . . . . 8
⊢ (𝑢 ∈ dom (◡ E ↾ 𝐴) → [𝑢](◡ E
↾ 𝐴) = 𝑢) |
7 | 6 | eleq2d 2830 |
. . . . . . 7
⊢ (𝑢 ∈ dom (◡ E ↾ 𝐴) → (𝐵 ∈ [𝑢](◡ E
↾ 𝐴) ↔ 𝐵 ∈ 𝑢)) |
8 | 6 | eqeq1d 2742 |
. . . . . . 7
⊢ (𝑢 ∈ dom (◡ E ↾ 𝐴) → ([𝑢](◡ E
↾ 𝐴) = [𝐵] ≀ (◡ E ↾ 𝐴) ↔ 𝑢 = [𝐵] ≀ (◡ E ↾ 𝐴))) |
9 | 7, 8 | imbi12d 344 |
. . . . . 6
⊢ (𝑢 ∈ dom (◡ E ↾ 𝐴) → ((𝐵 ∈ [𝑢](◡ E
↾ 𝐴) → [𝑢](◡ E ↾ 𝐴) = [𝐵] ≀ (◡ E ↾ 𝐴)) ↔ (𝐵 ∈ 𝑢 → 𝑢 = [𝐵] ≀ (◡ E ↾ 𝐴)))) |
10 | 9 | adantl 481 |
. . . . 5
⊢ (((𝐵 ∈ 𝑉 ∧ ElDisj 𝐴) ∧ 𝑢 ∈ dom (◡ E ↾ 𝐴)) → ((𝐵 ∈ [𝑢](◡ E
↾ 𝐴) → [𝑢](◡ E ↾ 𝐴) = [𝐵] ≀ (◡ E ↾ 𝐴)) ↔ (𝐵 ∈ 𝑢 → 𝑢 = [𝐵] ≀ (◡ E ↾ 𝐴)))) |
11 | 5, 10 | mpbid 232 |
. . . 4
⊢ (((𝐵 ∈ 𝑉 ∧ ElDisj 𝐴) ∧ 𝑢 ∈ dom (◡ E ↾ 𝐴)) → (𝐵 ∈ 𝑢 → 𝑢 = [𝐵] ≀ (◡ E ↾ 𝐴))) |
12 | | df-coels 38368 |
. . . . . 6
⊢ ∼
𝐴 = ≀ (◡ E ↾ 𝐴) |
13 | 12 | eceq2i 8805 |
. . . . 5
⊢ [𝐵] ∼ 𝐴 = [𝐵] ≀ (◡ E ↾ 𝐴) |
14 | 13 | eqeq2i 2753 |
. . . 4
⊢ (𝑢 = [𝐵] ∼ 𝐴 ↔ 𝑢 = [𝐵] ≀ (◡ E ↾ 𝐴)) |
15 | 11, 14 | imbitrrdi 252 |
. . 3
⊢ (((𝐵 ∈ 𝑉 ∧ ElDisj 𝐴) ∧ 𝑢 ∈ dom (◡ E ↾ 𝐴)) → (𝐵 ∈ 𝑢 → 𝑢 = [𝐵] ∼ 𝐴)) |
16 | 15 | expimpd 453 |
. 2
⊢ ((𝐵 ∈ 𝑉 ∧ ElDisj 𝐴) → ((𝑢 ∈ dom (◡ E ↾ 𝐴) ∧ 𝐵 ∈ 𝑢) → 𝑢 = [𝐵] ∼ 𝐴)) |
17 | 16 | ex 412 |
1
⊢ (𝐵 ∈ 𝑉 → ( ElDisj 𝐴 → ((𝑢 ∈ dom (◡ E ↾ 𝐴) ∧ 𝐵 ∈ 𝑢) → 𝑢 = [𝐵] ∼ 𝐴))) |