Proof of Theorem ud3lem3b
| Step | Hyp | Ref
| Expression |
| 1 | | ud3lem0c 271 |
. . 3
(a →3 b)⊥ = (((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a⊥ ∪ (a ∩ b⊥ ))) |
| 2 | 1 | ran 71 |
. 2
((a →3 b)⊥ ∩ (a ∪ b)⊥ ) = ((((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a⊥ ∪ (a ∩ b⊥ ))) ∩ (a ∪ b)⊥ ) |
| 3 | | an32 76 |
. . 3
((((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a⊥ ∪ (a ∩ b⊥ ))) ∩ (a ∪ b)⊥ ) = ((((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a ∪ b)⊥ ) ∩ (a⊥ ∪ (a ∩ b⊥ ))) |
| 4 | | anass 69 |
. . . . . 6
(((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a ∪ b)⊥ ) = ((a ∪ b⊥ ) ∩ ((a ∪ b) ∩
(a ∪ b)⊥ )) |
| 5 | | dff 93 |
. . . . . . . . 9
0 = ((a ∪ b) ∩ (a
∪ b)⊥ ) |
| 6 | 5 | ax-r1 34 |
. . . . . . . 8
((a ∪ b) ∩ (a
∪ b)⊥ ) = 0 |
| 7 | 6 | lan 70 |
. . . . . . 7
((a ∪ b⊥ ) ∩ ((a ∪ b) ∩
(a ∪ b)⊥ )) = ((a ∪ b⊥ ) ∩ 0) |
| 8 | | an0 100 |
. . . . . . 7
((a ∪ b⊥ ) ∩ 0) = 0 |
| 9 | 7, 8 | ax-r2 35 |
. . . . . 6
((a ∪ b⊥ ) ∩ ((a ∪ b) ∩
(a ∪ b)⊥ )) = 0 |
| 10 | 4, 9 | ax-r2 35 |
. . . . 5
(((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a ∪ b)⊥ ) = 0 |
| 11 | 10 | ran 71 |
. . . 4
((((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a ∪ b)⊥ ) ∩ (a⊥ ∪ (a ∩ b⊥ ))) = (0 ∩ (a⊥ ∪ (a ∩ b⊥ ))) |
| 12 | | an0r 101 |
. . . 4
(0 ∩ (a⊥ ∪
(a ∩ b⊥ ))) = 0 |
| 13 | 11, 12 | ax-r2 35 |
. . 3
((((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a ∪ b)⊥ ) ∩ (a⊥ ∪ (a ∩ b⊥ ))) = 0 |
| 14 | 3, 13 | ax-r2 35 |
. 2
((((a ∪ b⊥ ) ∩ (a ∪ b))
∩ (a⊥ ∪ (a ∩ b⊥ ))) ∩ (a ∪ b)⊥ ) = 0 |
| 15 | 2, 14 | ax-r2 35 |
1
((a →3 b)⊥ ∩ (a ∪ b)⊥ ) = 0 |