Proof of Theorem nom13
| Step | Hyp | Ref
| Expression |
| 1 | | oran 79 |
. . . . . . . . 9
(a ∪ (a ∩ b)) =
(a⊥ ∩ (a ∩ b)⊥ )⊥ |
| 2 | 1 | ax-r1 34 |
. . . . . . . 8
(a⊥ ∩ (a ∩ b)⊥ )⊥ = (a ∪ (a ∩
b)) |
| 3 | | a5b 112 |
. . . . . . . 8
(a ∪ (a ∩ b)) =
a |
| 4 | 2, 3 | ax-r2 35 |
. . . . . . 7
(a⊥ ∩ (a ∩ b)⊥ )⊥ = a |
| 5 | 4 | con3 65 |
. . . . . 6
(a⊥ ∩ (a ∩ b)⊥ ) = a⊥ |
| 6 | 5 | lor 66 |
. . . . 5
((a⊥ ∩ (a ∩ b))
∪ (a⊥ ∩ (a ∩ b)⊥ )) = ((a⊥ ∩ (a ∩ b))
∪ a⊥ ) |
| 7 | | lea 152 |
. . . . . 6
(a⊥ ∩ (a ∩ b)) ≤
a⊥ |
| 8 | 7 | df-le2 123 |
. . . . 5
((a⊥ ∩ (a ∩ b))
∪ a⊥ ) = a⊥ |
| 9 | 6, 8 | ax-r2 35 |
. . . 4
((a⊥ ∩ (a ∩ b))
∪ (a⊥ ∩ (a ∩ b)⊥ )) = a⊥ |
| 10 | 9 | ax-r5 37 |
. . 3
(((a⊥ ∩ (a ∩ b))
∪ (a⊥ ∩ (a ∩ b)⊥ )) ∪ (a ∩ (a⊥ ∪ (a ∩ b)))) =
(a⊥ ∪ (a ∩ (a⊥ ∪ (a ∩ b)))) |
| 11 | | womaa 214 |
. . 3
(a⊥ ∪ (a ∩ (a⊥ ∪ (a ∩ b)))) =
(a⊥ ∪ (a ∩ b)) |
| 12 | 10, 11 | ax-r2 35 |
. 2
(((a⊥ ∩ (a ∩ b))
∪ (a⊥ ∩ (a ∩ b)⊥ )) ∪ (a ∩ (a⊥ ∪ (a ∩ b)))) =
(a⊥ ∪ (a ∩ b)) |
| 13 | | df-i3 45 |
. 2
(a →3 (a ∩ b)) =
(((a⊥ ∩ (a ∩ b))
∪ (a⊥ ∩ (a ∩ b)⊥ )) ∪ (a ∩ (a⊥ ∪ (a ∩ b)))) |
| 14 | | df-i1 43 |
. 2
(a →1 b) = (a⊥ ∪ (a ∩ b)) |
| 15 | 12, 13, 14 | 3tr1 60 |
1
(a →3 (a ∩ b)) =
(a →1 b) |