Proof of Theorem ud4lem1d
| Step | Hyp | Ref
| Expression |
| 1 | | ud4lem1c 579 |
. . 3
((a →4 b)⊥ ∪ (b →4 a)) = (a ∪
b⊥ ) |
| 2 | | ud4lem0c 280 |
. . 3
(b →4 a)⊥ = (((b⊥ ∪ a⊥ ) ∩ (b ∪ a⊥ )) ∩ ((b ∩ a⊥ ) ∪ a)) |
| 3 | 1, 2 | 2an 79 |
. 2
(((a →4 b)⊥ ∪ (b →4 a)) ∩ (b
→4 a)⊥ ) =
((a ∪ b⊥ ) ∩ (((b⊥ ∪ a⊥ ) ∩ (b ∪ a⊥ )) ∩ ((b ∩ a⊥ ) ∪ a))) |
| 4 | | an12 81 |
. . 3
((a ∪ b⊥ ) ∩ (((b⊥ ∪ a⊥ ) ∩ (b ∪ a⊥ )) ∩ ((b ∩ a⊥ ) ∪ a))) = (((b⊥ ∪ a⊥ ) ∩ (b ∪ a⊥ )) ∩ ((a ∪ b⊥ ) ∩ ((b ∩ a⊥ ) ∪ a))) |
| 5 | | ax-a2 31 |
. . . . 5
(b⊥ ∪ a⊥ ) = (a⊥ ∪ b⊥ ) |
| 6 | | ax-a2 31 |
. . . . 5
(b ∪ a⊥ ) = (a⊥ ∪ b) |
| 7 | 5, 6 | 2an 79 |
. . . 4
((b⊥ ∪ a⊥ ) ∩ (b ∪ a⊥ )) = ((a⊥ ∪ b⊥ ) ∩ (a⊥ ∪ b)) |
| 8 | | comor2 462 |
. . . . . . . . 9
(a ∪ b⊥ ) C b⊥ |
| 9 | 8 | comcom3 454 |
. . . . . . . 8
(a ∪ b⊥ )⊥ C
b⊥ |
| 10 | 9 | comcom5 458 |
. . . . . . 7
(a ∪ b⊥ ) C b |
| 11 | | comor1 461 |
. . . . . . . 8
(a ∪ b⊥ ) C a |
| 12 | 11 | comcom2 183 |
. . . . . . 7
(a ∪ b⊥ ) C a⊥ |
| 13 | 10, 12 | com2an 484 |
. . . . . 6
(a ∪ b⊥ ) C (b ∩ a⊥ ) |
| 14 | 13, 11 | fh1 469 |
. . . . 5
((a ∪ b⊥ ) ∩ ((b ∩ a⊥ ) ∪ a)) = (((a ∪
b⊥ ) ∩ (b ∩ a⊥ )) ∪ ((a ∪ b⊥ ) ∩ a)) |
| 15 | | ax-a2 31 |
. . . . . . . . 9
(a ∪ b⊥ ) = (b⊥ ∪ a) |
| 16 | | anor1 88 |
. . . . . . . . 9
(b ∩ a⊥ ) = (b⊥ ∪ a)⊥ |
| 17 | 15, 16 | 2an 79 |
. . . . . . . 8
((a ∪ b⊥ ) ∩ (b ∩ a⊥ )) = ((b⊥ ∪ a) ∩ (b⊥ ∪ a)⊥ ) |
| 18 | | dff 101 |
. . . . . . . . 9
0 = ((b⊥ ∪
a) ∩ (b⊥ ∪ a)⊥ ) |
| 19 | 18 | ax-r1 35 |
. . . . . . . 8
((b⊥ ∪ a) ∩ (b⊥ ∪ a)⊥ ) = 0 |
| 20 | 17, 19 | ax-r2 36 |
. . . . . . 7
((a ∪ b⊥ ) ∩ (b ∩ a⊥ )) = 0 |
| 21 | | ancom 74 |
. . . . . . . 8
((a ∪ b⊥ ) ∩ a) = (a ∩
(a ∪ b⊥ )) |
| 22 | | anabs 121 |
. . . . . . . 8
(a ∩ (a ∪ b⊥ )) = a |
| 23 | 21, 22 | ax-r2 36 |
. . . . . . 7
((a ∪ b⊥ ) ∩ a) = a |
| 24 | 20, 23 | 2or 72 |
. . . . . 6
(((a ∪ b⊥ ) ∩ (b ∩ a⊥ )) ∪ ((a ∪ b⊥ ) ∩ a)) = (0 ∪ a) |
| 25 | | ax-a2 31 |
. . . . . . 7
(0 ∪ a) = (a ∪ 0) |
| 26 | | or0 102 |
. . . . . . 7
(a ∪ 0) = a |
| 27 | 25, 26 | ax-r2 36 |
. . . . . 6
(0 ∪ a) = a |
| 28 | 24, 27 | ax-r2 36 |
. . . . 5
(((a ∪ b⊥ ) ∩ (b ∩ a⊥ )) ∪ ((a ∪ b⊥ ) ∩ a)) = a |
| 29 | 14, 28 | ax-r2 36 |
. . . 4
((a ∪ b⊥ ) ∩ ((b ∩ a⊥ ) ∪ a)) = a |
| 30 | 7, 29 | 2an 79 |
. . 3
(((b⊥ ∪
a⊥ ) ∩ (b ∪ a⊥ )) ∩ ((a ∪ b⊥ ) ∩ ((b ∩ a⊥ ) ∪ a))) = (((a⊥ ∪ b⊥ ) ∩ (a⊥ ∪ b)) ∩ a) |
| 31 | 4, 30 | ax-r2 36 |
. 2
((a ∪ b⊥ ) ∩ (((b⊥ ∪ a⊥ ) ∩ (b ∪ a⊥ )) ∩ ((b ∩ a⊥ ) ∪ a))) = (((a⊥ ∪ b⊥ ) ∩ (a⊥ ∪ b)) ∩ a) |
| 32 | 3, 31 | ax-r2 36 |
1
(((a →4 b)⊥ ∪ (b →4 a)) ∩ (b
→4 a)⊥ ) =
(((a⊥ ∪ b⊥ ) ∩ (a⊥ ∪ b)) ∩ a) |