Proof of Theorem u4lemana
| Step | Hyp | Ref
| Expression |
| 1 | | df-i4 47 |
. . 3
(a →4 b) = (((a ∩
b) ∪ (a⊥ ∩ b)) ∪ ((a⊥ ∪ b) ∩ b⊥ )) |
| 2 | 1 | ran 78 |
. 2
((a →4 b) ∩ a⊥ ) = ((((a ∩ b) ∪
(a⊥ ∩ b)) ∪ ((a⊥ ∪ b) ∩ b⊥ )) ∩ a⊥ ) |
| 3 | | comanr1 464 |
. . . . . . 7
a C (a ∩ b) |
| 4 | 3 | comcom3 454 |
. . . . . 6
a⊥ C
(a ∩ b) |
| 5 | | comanr1 464 |
. . . . . 6
a⊥ C
(a⊥ ∩ b) |
| 6 | 4, 5 | com2or 483 |
. . . . 5
a⊥ C
((a ∩ b) ∪ (a⊥ ∩ b)) |
| 7 | 6 | comcom 453 |
. . . 4
((a ∩ b) ∪ (a⊥ ∩ b)) C a⊥ |
| 8 | | comor1 461 |
. . . . . . . . 9
(a⊥ ∪ b) C a⊥ |
| 9 | 8 | comcom7 460 |
. . . . . . . 8
(a⊥ ∪ b) C a |
| 10 | | comor2 462 |
. . . . . . . 8
(a⊥ ∪ b) C b |
| 11 | 9, 10 | com2an 484 |
. . . . . . 7
(a⊥ ∪ b) C (a
∩ b) |
| 12 | 8, 10 | com2an 484 |
. . . . . . 7
(a⊥ ∪ b) C (a⊥ ∩ b) |
| 13 | 11, 12 | com2or 483 |
. . . . . 6
(a⊥ ∪ b) C ((a
∩ b) ∪ (a⊥ ∩ b)) |
| 14 | 13 | comcom 453 |
. . . . 5
((a ∩ b) ∪ (a⊥ ∩ b)) C (a⊥ ∪ b) |
| 15 | | comanr2 465 |
. . . . . . . 8
b C (a ∩ b) |
| 16 | 15 | comcom3 454 |
. . . . . . 7
b⊥ C
(a ∩ b) |
| 17 | | comanr2 465 |
. . . . . . . 8
b C (a⊥ ∩ b) |
| 18 | 17 | comcom3 454 |
. . . . . . 7
b⊥ C
(a⊥ ∩ b) |
| 19 | 16, 18 | com2or 483 |
. . . . . 6
b⊥ C
((a ∩ b) ∪ (a⊥ ∩ b)) |
| 20 | 19 | comcom 453 |
. . . . 5
((a ∩ b) ∪ (a⊥ ∩ b)) C b⊥ |
| 21 | 14, 20 | com2an 484 |
. . . 4
((a ∩ b) ∪ (a⊥ ∩ b)) C ((a⊥ ∪ b) ∩ b⊥ ) |
| 22 | 7, 21 | fh2r 474 |
. . 3
((((a ∩ b) ∪ (a⊥ ∩ b)) ∪ ((a⊥ ∪ b) ∩ b⊥ )) ∩ a⊥ ) = ((((a ∩ b) ∪
(a⊥ ∩ b)) ∩ a⊥ ) ∪ (((a⊥ ∪ b) ∩ b⊥ ) ∩ a⊥ )) |
| 23 | 4, 5 | fh1r 473 |
. . . . . 6
(((a ∩ b) ∪ (a⊥ ∩ b)) ∩ a⊥ ) = (((a ∩ b) ∩
a⊥ ) ∪ ((a⊥ ∩ b) ∩ a⊥ )) |
| 24 | | an32 83 |
. . . . . . . . 9
((a ∩ b) ∩ a⊥ ) = ((a ∩ a⊥ ) ∩ b) |
| 25 | | ancom 74 |
. . . . . . . . . 10
((a ∩ a⊥ ) ∩ b) = (b ∩
(a ∩ a⊥ )) |
| 26 | | dff 101 |
. . . . . . . . . . . . 13
0 = (a ∩ a⊥ ) |
| 27 | 26 | ax-r1 35 |
. . . . . . . . . . . 12
(a ∩ a⊥ ) = 0 |
| 28 | 27 | lan 77 |
. . . . . . . . . . 11
(b ∩ (a ∩ a⊥ )) = (b ∩ 0) |
| 29 | | an0 108 |
. . . . . . . . . . 11
(b ∩ 0) = 0 |
| 30 | 28, 29 | ax-r2 36 |
. . . . . . . . . 10
(b ∩ (a ∩ a⊥ )) = 0 |
| 31 | 25, 30 | ax-r2 36 |
. . . . . . . . 9
((a ∩ a⊥ ) ∩ b) = 0 |
| 32 | 24, 31 | ax-r2 36 |
. . . . . . . 8
((a ∩ b) ∩ a⊥ ) = 0 |
| 33 | | an32 83 |
. . . . . . . . 9
((a⊥ ∩ b) ∩ a⊥ ) = ((a⊥ ∩ a⊥ ) ∩ b) |
| 34 | | anidm 111 |
. . . . . . . . . 10
(a⊥ ∩ a⊥ ) = a⊥ |
| 35 | 34 | ran 78 |
. . . . . . . . 9
((a⊥ ∩ a⊥ ) ∩ b) = (a⊥ ∩ b) |
| 36 | 33, 35 | ax-r2 36 |
. . . . . . . 8
((a⊥ ∩ b) ∩ a⊥ ) = (a⊥ ∩ b) |
| 37 | 32, 36 | 2or 72 |
. . . . . . 7
(((a ∩ b) ∩ a⊥ ) ∪ ((a⊥ ∩ b) ∩ a⊥ )) = (0 ∪ (a⊥ ∩ b)) |
| 38 | | ax-a2 31 |
. . . . . . . 8
(0 ∪ (a⊥ ∩
b)) = ((a⊥ ∩ b) ∪ 0) |
| 39 | | or0 102 |
. . . . . . . 8
((a⊥ ∩ b) ∪ 0) = (a⊥ ∩ b) |
| 40 | 38, 39 | ax-r2 36 |
. . . . . . 7
(0 ∪ (a⊥ ∩
b)) = (a⊥ ∩ b) |
| 41 | 37, 40 | ax-r2 36 |
. . . . . 6
(((a ∩ b) ∩ a⊥ ) ∪ ((a⊥ ∩ b) ∩ a⊥ )) = (a⊥ ∩ b) |
| 42 | 23, 41 | ax-r2 36 |
. . . . 5
(((a ∩ b) ∪ (a⊥ ∩ b)) ∩ a⊥ ) = (a⊥ ∩ b) |
| 43 | | an32 83 |
. . . . . 6
(((a⊥ ∪
b) ∩ b⊥ ) ∩ a⊥ ) = (((a⊥ ∪ b) ∩ a⊥ ) ∩ b⊥ ) |
| 44 | | ancom 74 |
. . . . . . . 8
((a⊥ ∪ b) ∩ a⊥ ) = (a⊥ ∩ (a⊥ ∪ b)) |
| 45 | | leo 158 |
. . . . . . . . 9
a⊥ ≤ (a⊥ ∪ b) |
| 46 | 45 | df2le2 136 |
. . . . . . . 8
(a⊥ ∩ (a⊥ ∪ b)) = a⊥ |
| 47 | 44, 46 | ax-r2 36 |
. . . . . . 7
((a⊥ ∪ b) ∩ a⊥ ) = a⊥ |
| 48 | 47 | ran 78 |
. . . . . 6
(((a⊥ ∪
b) ∩ a⊥ ) ∩ b⊥ ) = (a⊥ ∩ b⊥ ) |
| 49 | 43, 48 | ax-r2 36 |
. . . . 5
(((a⊥ ∪
b) ∩ b⊥ ) ∩ a⊥ ) = (a⊥ ∩ b⊥ ) |
| 50 | 42, 49 | 2or 72 |
. . . 4
((((a ∩ b) ∪ (a⊥ ∩ b)) ∩ a⊥ ) ∪ (((a⊥ ∪ b) ∩ b⊥ ) ∩ a⊥ )) = ((a⊥ ∩ b) ∪ (a⊥ ∩ b⊥ )) |
| 51 | | id 59 |
. . . 4
((a⊥ ∩ b) ∪ (a⊥ ∩ b⊥ )) = ((a⊥ ∩ b) ∪ (a⊥ ∩ b⊥ )) |
| 52 | 50, 51 | ax-r2 36 |
. . 3
((((a ∩ b) ∪ (a⊥ ∩ b)) ∩ a⊥ ) ∪ (((a⊥ ∪ b) ∩ b⊥ ) ∩ a⊥ )) = ((a⊥ ∩ b) ∪ (a⊥ ∩ b⊥ )) |
| 53 | 22, 52 | ax-r2 36 |
. 2
((((a ∩ b) ∪ (a⊥ ∩ b)) ∪ ((a⊥ ∪ b) ∩ b⊥ )) ∩ a⊥ ) = ((a⊥ ∩ b) ∪ (a⊥ ∩ b⊥ )) |
| 54 | 2, 53 | ax-r2 36 |
1
((a →4 b) ∩ a⊥ ) = ((a⊥ ∩ b) ∪ (a⊥ ∩ b⊥ )) |