Proof of Theorem ud1lem1
| Step | Hyp | Ref
| Expression |
| 1 | | df-i1 43 |
. 2
((a →1 b) →1 (b →1 a)) = ((a
→1 b)⊥
∪ ((a →1 b) ∩ (b
→1 a))) |
| 2 | | ud1lem0c 269 |
. . . 4
(a →1 b)⊥ = (a ∩ (a⊥ ∪ b⊥ )) |
| 3 | | df-i1 43 |
. . . . 5
(a →1 b) = (a⊥ ∪ (a ∩ b)) |
| 4 | | df-i1 43 |
. . . . 5
(b →1 a) = (b⊥ ∪ (b ∩ a)) |
| 5 | 3, 4 | 2an 72 |
. . . 4
((a →1 b) ∩ (b
→1 a)) = ((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (b ∩ a))) |
| 6 | 2, 5 | 2or 67 |
. . 3
((a →1 b)⊥ ∪ ((a →1 b) ∩ (b
→1 a))) = ((a ∩ (a⊥ ∪ b⊥ )) ∪ ((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (b ∩ a)))) |
| 7 | | ancom 68 |
. . . . . . . 8
(b ∩ a) = (a ∩
b) |
| 8 | 7 | lor 66 |
. . . . . . 7
(b⊥ ∪ (b ∩ a)) =
(b⊥ ∪ (a ∩ b)) |
| 9 | 8 | lan 70 |
. . . . . 6
((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (b ∩ a))) =
((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (a ∩ b))) |
| 10 | | coman1 177 |
. . . . . . . . 9
(a ∩ b) C a |
| 11 | 10 | comcom2 175 |
. . . . . . . 8
(a ∩ b) C a⊥ |
| 12 | | coman2 178 |
. . . . . . . . 9
(a ∩ b) C b |
| 13 | 12 | comcom2 175 |
. . . . . . . 8
(a ∩ b) C b⊥ |
| 14 | 11, 13 | fh3r 457 |
. . . . . . 7
((a⊥ ∩ b⊥ ) ∪ (a ∩ b)) =
((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (a ∩ b))) |
| 15 | 14 | ax-r1 34 |
. . . . . 6
((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (a ∩ b))) =
((a⊥ ∩ b⊥ ) ∪ (a ∩ b)) |
| 16 | 9, 15 | ax-r2 35 |
. . . . 5
((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (b ∩ a))) =
((a⊥ ∩ b⊥ ) ∪ (a ∩ b)) |
| 17 | 16 | lor 66 |
. . . 4
((a ∩ (a⊥ ∪ b⊥ )) ∪ ((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (b ∩ a)))) =
((a ∩ (a⊥ ∪ b⊥ )) ∪ ((a⊥ ∩ b⊥ ) ∪ (a ∩ b))) |
| 18 | | or12 73 |
. . . . 5
((a ∩ (a⊥ ∪ b⊥ )) ∪ ((a⊥ ∩ b⊥ ) ∪ (a ∩ b))) =
((a⊥ ∩ b⊥ ) ∪ ((a ∩ (a⊥ ∪ b⊥ )) ∪ (a ∩ b))) |
| 19 | 10 | comcom 435 |
. . . . . . . 8
a C (a ∩ b) |
| 20 | | comorr 176 |
. . . . . . . . . 10
a⊥ C (a⊥ ∪ b⊥ ) |
| 21 | 20 | comcom2 175 |
. . . . . . . . 9
a⊥ C (a⊥ ∪ b⊥ )⊥ |
| 22 | 21 | comcom5 440 |
. . . . . . . 8
a C (a⊥ ∪ b⊥ ) |
| 23 | 19, 22 | fh4r 458 |
. . . . . . 7
((a ∩ (a⊥ ∪ b⊥ )) ∪ (a ∩ b)) =
((a ∪ (a ∩ b))
∩ ((a⊥ ∪ b⊥ ) ∪ (a ∩ b))) |
| 24 | 23 | lor 66 |
. . . . . 6
((a⊥ ∩ b⊥ ) ∪ ((a ∩ (a⊥ ∪ b⊥ )) ∪ (a ∩ b))) =
((a⊥ ∩ b⊥ ) ∪ ((a ∪ (a ∩
b)) ∩ ((a⊥ ∪ b⊥ ) ∪ (a ∩ b)))) |
| 25 | | a5b 112 |
. . . . . . . . . 10
(a ∪ (a ∩ b)) =
a |
| 26 | | df-a 39 |
. . . . . . . . . . . 12
(a ∩ b) = (a⊥ ∪ b⊥ )⊥ |
| 27 | 26 | lor 66 |
. . . . . . . . . . 11
((a⊥ ∪ b⊥ ) ∪ (a ∩ b)) =
((a⊥ ∪ b⊥ ) ∪ (a⊥ ∪ b⊥ )⊥ ) |
| 28 | | df-t 40 |
. . . . . . . . . . . 12
1 = ((a⊥ ∪ b⊥ ) ∪ (a⊥ ∪ b⊥ )⊥ ) |
| 29 | 28 | ax-r1 34 |
. . . . . . . . . . 11
((a⊥ ∪ b⊥ ) ∪ (a⊥ ∪ b⊥ )⊥ ) =
1 |
| 30 | 27, 29 | ax-r2 35 |
. . . . . . . . . 10
((a⊥ ∪ b⊥ ) ∪ (a ∩ b)) =
1 |
| 31 | 25, 30 | 2an 72 |
. . . . . . . . 9
((a ∪ (a ∩ b))
∩ ((a⊥ ∪ b⊥ ) ∪ (a ∩ b))) =
(a ∩ 1) |
| 32 | | an1 98 |
. . . . . . . . 9
(a ∩ 1) = a |
| 33 | 31, 32 | ax-r2 35 |
. . . . . . . 8
((a ∪ (a ∩ b))
∩ ((a⊥ ∪ b⊥ ) ∪ (a ∩ b))) =
a |
| 34 | 33 | lor 66 |
. . . . . . 7
((a⊥ ∩ b⊥ ) ∪ ((a ∪ (a ∩
b)) ∩ ((a⊥ ∪ b⊥ ) ∪ (a ∩ b)))) =
((a⊥ ∩ b⊥ ) ∪ a) |
| 35 | | ax-a2 30 |
. . . . . . 7
((a⊥ ∩ b⊥ ) ∪ a) = (a ∪
(a⊥ ∩ b⊥ )) |
| 36 | 34, 35 | ax-r2 35 |
. . . . . 6
((a⊥ ∩ b⊥ ) ∪ ((a ∪ (a ∩
b)) ∩ ((a⊥ ∪ b⊥ ) ∪ (a ∩ b)))) =
(a ∪ (a⊥ ∩ b⊥ )) |
| 37 | 24, 36 | ax-r2 35 |
. . . . 5
((a⊥ ∩ b⊥ ) ∪ ((a ∩ (a⊥ ∪ b⊥ )) ∪ (a ∩ b))) =
(a ∪ (a⊥ ∩ b⊥ )) |
| 38 | 18, 37 | ax-r2 35 |
. . . 4
((a ∩ (a⊥ ∪ b⊥ )) ∪ ((a⊥ ∩ b⊥ ) ∪ (a ∩ b))) =
(a ∪ (a⊥ ∩ b⊥ )) |
| 39 | 17, 38 | ax-r2 35 |
. . 3
((a ∩ (a⊥ ∪ b⊥ )) ∪ ((a⊥ ∪ (a ∩ b))
∩ (b⊥ ∪ (b ∩ a)))) =
(a ∪ (a⊥ ∩ b⊥ )) |
| 40 | 6, 39 | ax-r2 35 |
. 2
((a →1 b)⊥ ∪ ((a →1 b) ∩ (b
→1 a))) = (a ∪ (a⊥ ∩ b⊥ )) |
| 41 | 1, 40 | ax-r2 35 |
1
((a →1 b) →1 (b →1 a)) = (a ∪
(a⊥ ∩ b⊥ )) |