Proof of Theorem xpsfrnel
Step | Hyp | Ref
| Expression |
1 | | elixp2 8689 |
. 2
⊢ (𝐺 ∈ X𝑘 ∈
2o if(𝑘 =
∅, 𝐴, 𝐵) ↔ (𝐺 ∈ V ∧ 𝐺 Fn 2o ∧ ∀𝑘 ∈ 2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵))) |
2 | | 3ancoma 1097 |
. . 3
⊢ ((𝐺 ∈ V ∧ 𝐺 Fn 2o ∧
∀𝑘 ∈
2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵)) ↔ (𝐺 Fn 2o ∧ 𝐺 ∈ V ∧ ∀𝑘 ∈ 2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵))) |
3 | | 2onn 8472 |
. . . . . . . . . 10
⊢
2o ∈ ω |
4 | | nnfi 8950 |
. . . . . . . . . 10
⊢
(2o ∈ ω → 2o ∈
Fin) |
5 | 3, 4 | ax-mp 5 |
. . . . . . . . 9
⊢
2o ∈ Fin |
6 | | fnfi 8964 |
. . . . . . . . 9
⊢ ((𝐺 Fn 2o ∧
2o ∈ Fin) → 𝐺 ∈ Fin) |
7 | 5, 6 | mpan2 688 |
. . . . . . . 8
⊢ (𝐺 Fn 2o → 𝐺 ∈ Fin) |
8 | 7 | elexd 3452 |
. . . . . . 7
⊢ (𝐺 Fn 2o → 𝐺 ∈ V) |
9 | 8 | biantrurd 533 |
. . . . . 6
⊢ (𝐺 Fn 2o →
(∀𝑘 ∈
2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵) ↔ (𝐺 ∈ V ∧ ∀𝑘 ∈ 2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵)))) |
10 | | df2o3 8305 |
. . . . . . . 8
⊢
2o = {∅, 1o} |
11 | 10 | raleqi 3346 |
. . . . . . 7
⊢
(∀𝑘 ∈
2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵) ↔ ∀𝑘 ∈ {∅, 1o} (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵)) |
12 | | 0ex 5231 |
. . . . . . . 8
⊢ ∅
∈ V |
13 | | 1oex 8307 |
. . . . . . . 8
⊢
1o ∈ V |
14 | | fveq2 6774 |
. . . . . . . . 9
⊢ (𝑘 = ∅ → (𝐺‘𝑘) = (𝐺‘∅)) |
15 | | iftrue 4465 |
. . . . . . . . 9
⊢ (𝑘 = ∅ → if(𝑘 = ∅, 𝐴, 𝐵) = 𝐴) |
16 | 14, 15 | eleq12d 2833 |
. . . . . . . 8
⊢ (𝑘 = ∅ → ((𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵) ↔ (𝐺‘∅) ∈ 𝐴)) |
17 | | fveq2 6774 |
. . . . . . . . 9
⊢ (𝑘 = 1o → (𝐺‘𝑘) = (𝐺‘1o)) |
18 | | 1n0 8318 |
. . . . . . . . . . 11
⊢
1o ≠ ∅ |
19 | | neeq1 3006 |
. . . . . . . . . . 11
⊢ (𝑘 = 1o → (𝑘 ≠ ∅ ↔
1o ≠ ∅)) |
20 | 18, 19 | mpbiri 257 |
. . . . . . . . . 10
⊢ (𝑘 = 1o → 𝑘 ≠ ∅) |
21 | | ifnefalse 4471 |
. . . . . . . . . 10
⊢ (𝑘 ≠ ∅ → if(𝑘 = ∅, 𝐴, 𝐵) = 𝐵) |
22 | 20, 21 | syl 17 |
. . . . . . . . 9
⊢ (𝑘 = 1o → if(𝑘 = ∅, 𝐴, 𝐵) = 𝐵) |
23 | 17, 22 | eleq12d 2833 |
. . . . . . . 8
⊢ (𝑘 = 1o → ((𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵) ↔ (𝐺‘1o) ∈ 𝐵)) |
24 | 12, 13, 16, 23 | ralpr 4636 |
. . . . . . 7
⊢
(∀𝑘 ∈
{∅, 1o} (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵) ↔ ((𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵)) |
25 | 11, 24 | bitri 274 |
. . . . . 6
⊢
(∀𝑘 ∈
2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵) ↔ ((𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵)) |
26 | 9, 25 | bitr3di 286 |
. . . . 5
⊢ (𝐺 Fn 2o → ((𝐺 ∈ V ∧ ∀𝑘 ∈ 2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵)) ↔ ((𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵))) |
27 | 26 | pm5.32i 575 |
. . . 4
⊢ ((𝐺 Fn 2o ∧ (𝐺 ∈ V ∧ ∀𝑘 ∈ 2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵))) ↔ (𝐺 Fn 2o ∧ ((𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵))) |
28 | | 3anass 1094 |
. . . 4
⊢ ((𝐺 Fn 2o ∧ 𝐺 ∈ V ∧ ∀𝑘 ∈ 2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵)) ↔ (𝐺 Fn 2o ∧ (𝐺 ∈ V ∧ ∀𝑘 ∈ 2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵)))) |
29 | | 3anass 1094 |
. . . 4
⊢ ((𝐺 Fn 2o ∧ (𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵) ↔ (𝐺 Fn 2o ∧ ((𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵))) |
30 | 27, 28, 29 | 3bitr4i 303 |
. . 3
⊢ ((𝐺 Fn 2o ∧ 𝐺 ∈ V ∧ ∀𝑘 ∈ 2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵)) ↔ (𝐺 Fn 2o ∧ (𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵)) |
31 | 2, 30 | bitri 274 |
. 2
⊢ ((𝐺 ∈ V ∧ 𝐺 Fn 2o ∧
∀𝑘 ∈
2o (𝐺‘𝑘) ∈ if(𝑘 = ∅, 𝐴, 𝐵)) ↔ (𝐺 Fn 2o ∧ (𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵)) |
32 | 1, 31 | bitri 274 |
1
⊢ (𝐺 ∈ X𝑘 ∈
2o if(𝑘 =
∅, 𝐴, 𝐵) ↔ (𝐺 Fn 2o ∧ (𝐺‘∅) ∈ 𝐴 ∧ (𝐺‘1o) ∈ 𝐵)) |