Step | Hyp | Ref
| Expression |
1 | | csbeq1 3835 |
. . . 4
⊢ (𝑦 = 𝐴 → ⦋𝑦 / 𝑥⦌(𝐵 ∩ 𝐶) = ⦋𝐴 / 𝑥⦌(𝐵 ∩ 𝐶)) |
2 | | csbeq1 3835 |
. . . . 5
⊢ (𝑦 = 𝐴 → ⦋𝑦 / 𝑥⦌𝐵 = ⦋𝐴 / 𝑥⦌𝐵) |
3 | | csbeq1 3835 |
. . . . 5
⊢ (𝑦 = 𝐴 → ⦋𝑦 / 𝑥⦌𝐶 = ⦋𝐴 / 𝑥⦌𝐶) |
4 | 2, 3 | ineq12d 4147 |
. . . 4
⊢ (𝑦 = 𝐴 → (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐶) = (⦋𝐴 / 𝑥⦌𝐵 ∩ ⦋𝐴 / 𝑥⦌𝐶)) |
5 | 1, 4 | eqeq12d 2754 |
. . 3
⊢ (𝑦 = 𝐴 → (⦋𝑦 / 𝑥⦌(𝐵 ∩ 𝐶) = (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐶) ↔ ⦋𝐴 / 𝑥⦌(𝐵 ∩ 𝐶) = (⦋𝐴 / 𝑥⦌𝐵 ∩ ⦋𝐴 / 𝑥⦌𝐶))) |
6 | | vex 3436 |
. . . 4
⊢ 𝑦 ∈ V |
7 | | nfcsb1v 3857 |
. . . . 5
⊢
Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐵 |
8 | | nfcsb1v 3857 |
. . . . 5
⊢
Ⅎ𝑥⦋𝑦 / 𝑥⦌𝐶 |
9 | 7, 8 | nfin 4150 |
. . . 4
⊢
Ⅎ𝑥(⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐶) |
10 | | csbeq1a 3846 |
. . . . 5
⊢ (𝑥 = 𝑦 → 𝐵 = ⦋𝑦 / 𝑥⦌𝐵) |
11 | | csbeq1a 3846 |
. . . . 5
⊢ (𝑥 = 𝑦 → 𝐶 = ⦋𝑦 / 𝑥⦌𝐶) |
12 | 10, 11 | ineq12d 4147 |
. . . 4
⊢ (𝑥 = 𝑦 → (𝐵 ∩ 𝐶) = (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐶)) |
13 | 6, 9, 12 | csbief 3867 |
. . 3
⊢
⦋𝑦 /
𝑥⦌(𝐵 ∩ 𝐶) = (⦋𝑦 / 𝑥⦌𝐵 ∩ ⦋𝑦 / 𝑥⦌𝐶) |
14 | 5, 13 | vtoclg 3505 |
. 2
⊢ (𝐴 ∈ V →
⦋𝐴 / 𝑥⦌(𝐵 ∩ 𝐶) = (⦋𝐴 / 𝑥⦌𝐵 ∩ ⦋𝐴 / 𝑥⦌𝐶)) |
15 | | csbprc 4340 |
. . 3
⊢ (¬
𝐴 ∈ V →
⦋𝐴 / 𝑥⦌(𝐵 ∩ 𝐶) = ∅) |
16 | | csbprc 4340 |
. . . . 5
⊢ (¬
𝐴 ∈ V →
⦋𝐴 / 𝑥⦌𝐵 = ∅) |
17 | | csbprc 4340 |
. . . . 5
⊢ (¬
𝐴 ∈ V →
⦋𝐴 / 𝑥⦌𝐶 = ∅) |
18 | 16, 17 | ineq12d 4147 |
. . . 4
⊢ (¬
𝐴 ∈ V →
(⦋𝐴 / 𝑥⦌𝐵 ∩ ⦋𝐴 / 𝑥⦌𝐶) = (∅ ∩
∅)) |
19 | | in0 4325 |
. . . 4
⊢ (∅
∩ ∅) = ∅ |
20 | 18, 19 | eqtr2di 2795 |
. . 3
⊢ (¬
𝐴 ∈ V → ∅ =
(⦋𝐴 / 𝑥⦌𝐵 ∩ ⦋𝐴 / 𝑥⦌𝐶)) |
21 | 15, 20 | eqtrd 2778 |
. 2
⊢ (¬
𝐴 ∈ V →
⦋𝐴 / 𝑥⦌(𝐵 ∩ 𝐶) = (⦋𝐴 / 𝑥⦌𝐵 ∩ ⦋𝐴 / 𝑥⦌𝐶)) |
22 | 14, 21 | pm2.61i 182 |
1
⊢
⦋𝐴 /
𝑥⦌(𝐵 ∩ 𝐶) = (⦋𝐴 / 𝑥⦌𝐵 ∩ ⦋𝐴 / 𝑥⦌𝐶) |