Proof of Theorem csbie2df
| Step | Hyp | Ref
| Expression |
| 1 | | csbie2df.a |
. 2
⊢ (𝜑 → 𝐴 ∈ 𝑉) |
| 2 | | eqidd 2738 |
. . 3
⊢ (𝜑 → 𝐷 = 𝐷) |
| 3 | | dfsbcq 3790 |
. . . . . 6
⊢ (𝑦 = 𝐴 → ([𝑦 / 𝑥]𝐵 = 𝐷 ↔ [𝐴 / 𝑥]𝐵 = 𝐷)) |
| 4 | | sbceqg 4412 |
. . . . . . . . 9
⊢ (𝐴 ∈ 𝑉 → ([𝐴 / 𝑥]𝐵 = 𝐷 ↔ ⦋𝐴 / 𝑥⦌𝐵 = ⦋𝐴 / 𝑥⦌𝐷)) |
| 5 | 4 | adantr 480 |
. . . . . . . 8
⊢ ((𝐴 ∈ 𝑉 ∧ 𝜑) → ([𝐴 / 𝑥]𝐵 = 𝐷 ↔ ⦋𝐴 / 𝑥⦌𝐵 = ⦋𝐴 / 𝑥⦌𝐷)) |
| 6 | | csbie2df.d |
. . . . . . . . . 10
⊢ (𝜑 → Ⅎ𝑥𝐷) |
| 7 | | csbtt 3916 |
. . . . . . . . . 10
⊢ ((𝐴 ∈ 𝑉 ∧ Ⅎ𝑥𝐷) → ⦋𝐴 / 𝑥⦌𝐷 = 𝐷) |
| 8 | 6, 7 | sylan2 593 |
. . . . . . . . 9
⊢ ((𝐴 ∈ 𝑉 ∧ 𝜑) → ⦋𝐴 / 𝑥⦌𝐷 = 𝐷) |
| 9 | 8 | eqeq2d 2748 |
. . . . . . . 8
⊢ ((𝐴 ∈ 𝑉 ∧ 𝜑) → (⦋𝐴 / 𝑥⦌𝐵 = ⦋𝐴 / 𝑥⦌𝐷 ↔ ⦋𝐴 / 𝑥⦌𝐵 = 𝐷)) |
| 10 | 5, 9 | bitrd 279 |
. . . . . . 7
⊢ ((𝐴 ∈ 𝑉 ∧ 𝜑) → ([𝐴 / 𝑥]𝐵 = 𝐷 ↔ ⦋𝐴 / 𝑥⦌𝐵 = 𝐷)) |
| 11 | 1, 10 | mpancom 688 |
. . . . . 6
⊢ (𝜑 → ([𝐴 / 𝑥]𝐵 = 𝐷 ↔ ⦋𝐴 / 𝑥⦌𝐵 = 𝐷)) |
| 12 | 3, 11 | sylan9bb 509 |
. . . . 5
⊢ ((𝑦 = 𝐴 ∧ 𝜑) → ([𝑦 / 𝑥]𝐵 = 𝐷 ↔ ⦋𝐴 / 𝑥⦌𝐵 = 𝐷)) |
| 13 | 12 | pm5.74da 804 |
. . . 4
⊢ (𝑦 = 𝐴 → ((𝜑 → [𝑦 / 𝑥]𝐵 = 𝐷) ↔ (𝜑 → ⦋𝐴 / 𝑥⦌𝐵 = 𝐷))) |
| 14 | | csbie2df.2 |
. . . . . . 7
⊢ ((𝜑 ∧ 𝑦 = 𝐴) → 𝐶 = 𝐷) |
| 15 | 14 | eqeq1d 2739 |
. . . . . 6
⊢ ((𝜑 ∧ 𝑦 = 𝐴) → (𝐶 = 𝐷 ↔ 𝐷 = 𝐷)) |
| 16 | 15 | expcom 413 |
. . . . 5
⊢ (𝑦 = 𝐴 → (𝜑 → (𝐶 = 𝐷 ↔ 𝐷 = 𝐷))) |
| 17 | 16 | pm5.74d 273 |
. . . 4
⊢ (𝑦 = 𝐴 → ((𝜑 → 𝐶 = 𝐷) ↔ (𝜑 → 𝐷 = 𝐷))) |
| 18 | | sbsbc 3792 |
. . . . . 6
⊢ ([𝑦 / 𝑥]𝐵 = 𝐷 ↔ [𝑦 / 𝑥]𝐵 = 𝐷) |
| 19 | | csbie2df.p |
. . . . . . 7
⊢
Ⅎ𝑥𝜑 |
| 20 | | csbie2df.c |
. . . . . . . 8
⊢ (𝜑 → Ⅎ𝑥𝐶) |
| 21 | 20, 6 | nfeqd 2916 |
. . . . . . 7
⊢ (𝜑 → Ⅎ𝑥 𝐶 = 𝐷) |
| 22 | | csbie2df.1 |
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑥 = 𝑦) → 𝐵 = 𝐶) |
| 23 | 22 | eqeq1d 2739 |
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑥 = 𝑦) → (𝐵 = 𝐷 ↔ 𝐶 = 𝐷)) |
| 24 | 23 | ex 412 |
. . . . . . 7
⊢ (𝜑 → (𝑥 = 𝑦 → (𝐵 = 𝐷 ↔ 𝐶 = 𝐷))) |
| 25 | 19, 21, 24 | sbiedw 2316 |
. . . . . 6
⊢ (𝜑 → ([𝑦 / 𝑥]𝐵 = 𝐷 ↔ 𝐶 = 𝐷)) |
| 26 | 18, 25 | bitr3id 285 |
. . . . 5
⊢ (𝜑 → ([𝑦 / 𝑥]𝐵 = 𝐷 ↔ 𝐶 = 𝐷)) |
| 27 | 26 | pm5.74i 271 |
. . . 4
⊢ ((𝜑 → [𝑦 / 𝑥]𝐵 = 𝐷) ↔ (𝜑 → 𝐶 = 𝐷)) |
| 28 | 13, 17, 27 | vtoclbg 3557 |
. . 3
⊢ (𝐴 ∈ 𝑉 → ((𝜑 → ⦋𝐴 / 𝑥⦌𝐵 = 𝐷) ↔ (𝜑 → 𝐷 = 𝐷))) |
| 29 | 2, 28 | mpbiri 258 |
. 2
⊢ (𝐴 ∈ 𝑉 → (𝜑 → ⦋𝐴 / 𝑥⦌𝐵 = 𝐷)) |
| 30 | 1, 29 | mpcom 38 |
1
⊢ (𝜑 → ⦋𝐴 / 𝑥⦌𝐵 = 𝐷) |