Proof of Theorem mhlem1
| Step | Hyp | Ref
| Expression |
| 1 | | df-t 40 |
. . . . 5
1 = (b ∪ b⊥ ) |
| 2 | 1 | lan 70 |
. . . 4
((a ∪ b) ∩ 1) = ((a ∪ b) ∩
(b ∪ b⊥ )) |
| 3 | | an1 98 |
. . . 4
((a ∪ b) ∩ 1) = (a
∪ b) |
| 4 | | comor2 444 |
. . . . . 6
(a ∪ b) C b |
| 5 | 4 | comcom2 175 |
. . . . . 6
(a ∪ b) C b⊥ |
| 6 | 4, 5 | fh1 451 |
. . . . 5
((a ∪ b) ∩ (b
∪ b⊥ )) = (((a ∪ b) ∩
b) ∪ ((a ∪ b) ∩
b⊥ )) |
| 7 | | ax-a2 30 |
. . . . 5
(((a ∪ b) ∩ b)
∪ ((a ∪ b) ∩ b⊥ )) = (((a ∪ b) ∩
b⊥ ) ∪ ((a ∪ b) ∩
b)) |
| 8 | | mhlem1.1 |
. . . . . . . . . 10
a C b |
| 9 | 8 | comcom2 175 |
. . . . . . . . 9
a C b⊥ |
| 10 | 9 | comcom 435 |
. . . . . . . 8
b⊥ C a |
| 11 | | comid 179 |
. . . . . . . . 9
b C b |
| 12 | 11 | comcom3 436 |
. . . . . . . 8
b⊥ C b |
| 13 | 10, 12 | fh1r 455 |
. . . . . . 7
((a ∪ b) ∩ b⊥ ) = ((a ∩ b⊥ ) ∪ (b ∩ b⊥ )) |
| 14 | | dff 93 |
. . . . . . . . 9
0 = (b ∩ b⊥ ) |
| 15 | 14 | lor 66 |
. . . . . . . 8
((a ∩ b⊥ ) ∪ 0) = ((a ∩ b⊥ ) ∪ (b ∩ b⊥ )) |
| 16 | 15 | ax-r1 34 |
. . . . . . 7
((a ∩ b⊥ ) ∪ (b ∩ b⊥ )) = ((a ∩ b⊥ ) ∪ 0) |
| 17 | | or0 94 |
. . . . . . 7
((a ∩ b⊥ ) ∪ 0) = (a ∩ b⊥ ) |
| 18 | 13, 16, 17 | 3tr 62 |
. . . . . 6
((a ∪ b) ∩ b⊥ ) = (a ∩ b⊥ ) |
| 19 | | ancom 68 |
. . . . . . 7
((a ∪ b) ∩ b) =
(b ∩ (a ∪ b)) |
| 20 | | ax-a2 30 |
. . . . . . . 8
(a ∪ b) = (b ∪
a) |
| 21 | 20 | lan 70 |
. . . . . . 7
(b ∩ (a ∪ b)) =
(b ∩ (b ∪ a)) |
| 22 | | a5c 113 |
. . . . . . 7
(b ∩ (b ∪ a)) =
b |
| 23 | 19, 21, 22 | 3tr 62 |
. . . . . 6
((a ∪ b) ∩ b) =
b |
| 24 | 18, 23 | 2or 67 |
. . . . 5
(((a ∪ b) ∩ b⊥ ) ∪ ((a ∪ b) ∩
b)) = ((a ∩ b⊥ ) ∪ b) |
| 25 | 6, 7, 24 | 3tr 62 |
. . . 4
((a ∪ b) ∩ (b
∪ b⊥ )) = ((a ∩ b⊥ ) ∪ b) |
| 26 | 2, 3, 25 | 3tr2 61 |
. . 3
(a ∪ b) = ((a ∩
b⊥ ) ∪ b) |
| 27 | 26 | ran 71 |
. 2
((a ∪ b) ∩ (b⊥ ∪ c)) = (((a ∩
b⊥ ) ∪ b) ∩ (b⊥ ∪ c)) |
| 28 | | comorr 176 |
. . . . 5
b⊥ C (b⊥ ∪ c) |
| 29 | 28 | comcom6 441 |
. . . 4
b C (b⊥ ∪ c) |
| 30 | | comanr2 447 |
. . . . 5
b⊥ C (a ∩ b⊥ ) |
| 31 | 30 | comcom6 441 |
. . . 4
b C (a ∩ b⊥ ) |
| 32 | 29, 31 | fh2rc 462 |
. . 3
(((a ∩ b⊥ ) ∪ b) ∩ (b⊥ ∪ c)) = (((a ∩
b⊥ ) ∩ (b⊥ ∪ c)) ∪ (b
∩ (b⊥ ∪ c))) |
| 33 | | leao2 155 |
. . . . 5
(a ∩ b⊥ ) ≤ (b⊥ ∪ c) |
| 34 | 33 | df2le2 128 |
. . . 4
((a ∩ b⊥ ) ∩ (b⊥ ∪ c)) = (a ∩
b⊥ ) |
| 35 | 34 | ax-r5 37 |
. . 3
(((a ∩ b⊥ ) ∩ (b⊥ ∪ c)) ∪ (b
∩ (b⊥ ∪ c))) = ((a ∩
b⊥ ) ∪ (b ∩ (b⊥ ∪ c))) |
| 36 | 32, 35 | ax-r2 35 |
. 2
(((a ∩ b⊥ ) ∪ b) ∩ (b⊥ ∪ c)) = ((a ∩
b⊥ ) ∪ (b ∩ (b⊥ ∪ c))) |
| 37 | 11 | comcom2 175 |
. . . . 5
b C b⊥ |
| 38 | | mhlem1.2 |
. . . . . 6
c C b |
| 39 | 38 | comcom 435 |
. . . . 5
b C c |
| 40 | 37, 39 | fh1 451 |
. . . 4
(b ∩ (b⊥ ∪ c)) = ((b ∩
b⊥ ) ∪ (b ∩ c)) |
| 41 | 14 | ax-r5 37 |
. . . . 5
(0 ∪ (b ∩ c)) = ((b ∩
b⊥ ) ∪ (b ∩ c)) |
| 42 | 41 | ax-r1 34 |
. . . 4
((b ∩ b⊥ ) ∪ (b ∩ c)) = (0
∪ (b ∩ c)) |
| 43 | | or0r 95 |
. . . 4
(0 ∪ (b ∩ c)) = (b ∩
c) |
| 44 | 40, 42, 43 | 3tr 62 |
. . 3
(b ∩ (b⊥ ∪ c)) = (b ∩
c) |
| 45 | 44 | lor 66 |
. 2
((a ∩ b⊥ ) ∪ (b ∩ (b⊥ ∪ c))) = ((a ∩
b⊥ ) ∪ (b ∩ c)) |
| 46 | 27, 36, 45 | 3tr 62 |
1
((a ∪ b) ∩ (b⊥ ∪ c)) = ((a ∩
b⊥ ) ∪ (b ∩ c)) |