Proof of Theorem u5lemnaa
| Step | Hyp | Ref
| Expression |
| 1 | | anor2 81 |
. 2
((a →5 b)⊥ ∩ a) = ((a
→5 b) ∪ a⊥ )⊥ |
| 2 | | u5lemona 611 |
. . . 4
((a →5 b) ∪ a⊥ ) = (a⊥ ∪ (a ∩ b)) |
| 3 | 2 | ax-r4 36 |
. . 3
((a →5 b) ∪ a⊥ )⊥ = (a⊥ ∪ (a ∩ b))⊥ |
| 4 | | anor1 80 |
. . . . 5
(a ∩ (a ∩ b)⊥ ) = (a⊥ ∪ (a ∩ b))⊥ |
| 5 | 4 | ax-r1 34 |
. . . 4
(a⊥ ∪ (a ∩ b))⊥ = (a ∩ (a ∩
b)⊥ ) |
| 6 | | df-a 39 |
. . . . . 6
(a ∩ b) = (a⊥ ∪ b⊥ )⊥ |
| 7 | 6 | con2 64 |
. . . . 5
(a ∩ b)⊥ = (a⊥ ∪ b⊥ ) |
| 8 | 7 | lan 70 |
. . . 4
(a ∩ (a ∩ b)⊥ ) = (a ∩ (a⊥ ∪ b⊥ )) |
| 9 | 5, 8 | ax-r2 35 |
. . 3
(a⊥ ∪ (a ∩ b))⊥ = (a ∩ (a⊥ ∪ b⊥ )) |
| 10 | 3, 9 | ax-r2 35 |
. 2
((a →5 b) ∪ a⊥ )⊥ = (a ∩ (a⊥ ∪ b⊥ )) |
| 11 | 1, 10 | ax-r2 35 |
1
((a →5 b)⊥ ∩ a) = (a ∩
(a⊥ ∪ b⊥ )) |