Proof of Theorem cdleme31so
Step | Hyp | Ref
| Expression |
1 | | nfcvd 2910 |
. . 3
⊢ (𝑋 ∈ 𝐵 → Ⅎ𝑥(℩𝑧 ∈ 𝐵 ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑋 ∧ 𝑊)) = 𝑋) → 𝑧 = (𝑁 ∨ (𝑋 ∧ 𝑊))))) |
2 | | oveq1 7278 |
. . . . . . . . 9
⊢ (𝑥 = 𝑋 → (𝑥 ∧ 𝑊) = (𝑋 ∧ 𝑊)) |
3 | 2 | oveq2d 7287 |
. . . . . . . 8
⊢ (𝑥 = 𝑋 → (𝑠 ∨ (𝑥 ∧ 𝑊)) = (𝑠 ∨ (𝑋 ∧ 𝑊))) |
4 | | id 22 |
. . . . . . . 8
⊢ (𝑥 = 𝑋 → 𝑥 = 𝑋) |
5 | 3, 4 | eqeq12d 2756 |
. . . . . . 7
⊢ (𝑥 = 𝑋 → ((𝑠 ∨ (𝑥 ∧ 𝑊)) = 𝑥 ↔ (𝑠 ∨ (𝑋 ∧ 𝑊)) = 𝑋)) |
6 | 5 | anbi2d 629 |
. . . . . 6
⊢ (𝑥 = 𝑋 → ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑥 ∧ 𝑊)) = 𝑥) ↔ (¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑋 ∧ 𝑊)) = 𝑋))) |
7 | 2 | oveq2d 7287 |
. . . . . . 7
⊢ (𝑥 = 𝑋 → (𝑁 ∨ (𝑥 ∧ 𝑊)) = (𝑁 ∨ (𝑋 ∧ 𝑊))) |
8 | 7 | eqeq2d 2751 |
. . . . . 6
⊢ (𝑥 = 𝑋 → (𝑧 = (𝑁 ∨ (𝑥 ∧ 𝑊)) ↔ 𝑧 = (𝑁 ∨ (𝑋 ∧ 𝑊)))) |
9 | 6, 8 | imbi12d 345 |
. . . . 5
⊢ (𝑥 = 𝑋 → (((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑥 ∧ 𝑊)) = 𝑥) → 𝑧 = (𝑁 ∨ (𝑥 ∧ 𝑊))) ↔ ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑋 ∧ 𝑊)) = 𝑋) → 𝑧 = (𝑁 ∨ (𝑋 ∧ 𝑊))))) |
10 | 9 | ralbidv 3123 |
. . . 4
⊢ (𝑥 = 𝑋 → (∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑥 ∧ 𝑊)) = 𝑥) → 𝑧 = (𝑁 ∨ (𝑥 ∧ 𝑊))) ↔ ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑋 ∧ 𝑊)) = 𝑋) → 𝑧 = (𝑁 ∨ (𝑋 ∧ 𝑊))))) |
11 | 10 | riotabidv 7230 |
. . 3
⊢ (𝑥 = 𝑋 → (℩𝑧 ∈ 𝐵 ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑥 ∧ 𝑊)) = 𝑥) → 𝑧 = (𝑁 ∨ (𝑥 ∧ 𝑊)))) = (℩𝑧 ∈ 𝐵 ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑋 ∧ 𝑊)) = 𝑋) → 𝑧 = (𝑁 ∨ (𝑋 ∧ 𝑊))))) |
12 | 1, 11 | csbiegf 3871 |
. 2
⊢ (𝑋 ∈ 𝐵 → ⦋𝑋 / 𝑥⦌(℩𝑧 ∈ 𝐵 ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑥 ∧ 𝑊)) = 𝑥) → 𝑧 = (𝑁 ∨ (𝑥 ∧ 𝑊)))) = (℩𝑧 ∈ 𝐵 ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑋 ∧ 𝑊)) = 𝑋) → 𝑧 = (𝑁 ∨ (𝑋 ∧ 𝑊))))) |
13 | | cdleme31so.o |
. . 3
⊢ 𝑂 = (℩𝑧 ∈ 𝐵 ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑥 ∧ 𝑊)) = 𝑥) → 𝑧 = (𝑁 ∨ (𝑥 ∧ 𝑊)))) |
14 | 13 | csbeq2i 3845 |
. 2
⊢
⦋𝑋 /
𝑥⦌𝑂 = ⦋𝑋 / 𝑥⦌(℩𝑧 ∈ 𝐵 ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑥 ∧ 𝑊)) = 𝑥) → 𝑧 = (𝑁 ∨ (𝑥 ∧ 𝑊)))) |
15 | | cdleme31so.c |
. 2
⊢ 𝐶 = (℩𝑧 ∈ 𝐵 ∀𝑠 ∈ 𝐴 ((¬ 𝑠 ≤ 𝑊 ∧ (𝑠 ∨ (𝑋 ∧ 𝑊)) = 𝑋) → 𝑧 = (𝑁 ∨ (𝑋 ∧ 𝑊)))) |
16 | 12, 14, 15 | 3eqtr4g 2805 |
1
⊢ (𝑋 ∈ 𝐵 → ⦋𝑋 / 𝑥⦌𝑂 = 𝐶) |