Proof of Theorem oa23
| Step | Hyp | Ref
| Expression |
| 1 | | ax-a2 31 |
. . . . . . 7
(b ∪ c) = (c ∪
b) |
| 2 | 1 | ax-r4 37 |
. . . . . 6
(b ∪ c)⊥ = (c ∪ b)⊥ |
| 3 | | ancom 74 |
. . . . . 6
((a →2 b) ∩ (a
→2 c)) = ((a →2 c) ∩ (a
→2 b)) |
| 4 | 2, 3 | 2or 72 |
. . . . 5
((b ∪ c)⊥ ∪ ((a →2 b) ∩ (a
→2 c))) = ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))) |
| 5 | 4 | lan 77 |
. . . 4
((a →2 b) ∩ ((b
∪ c)⊥ ∪ ((a →2 b) ∩ (a
→2 c)))) = ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))) |
| 6 | 5 | ax-r5 38 |
. . 3
(((a →2 b) ∩ ((b
∪ c)⊥ ∪ ((a →2 b) ∩ (a
→2 c)))) ∪ (a →2 c)) = (((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))) ∪ (a →2 c)) |
| 7 | | ax-a2 31 |
. . 3
(((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))) ∪ (a →2 c)) = ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) |
| 8 | | ax-a3 32 |
. . . . . . . . . 10
(((a →2 c) ∪ (a
→2 c)) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) = ((a →2 c) ∪ ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) |
| 9 | 8 | ax-r1 35 |
. . . . . . . . 9
((a →2 c) ∪ ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) = (((a →2 c) ∪ (a
→2 c)) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) |
| 10 | | oridm 110 |
. . . . . . . . . 10
((a →2 c) ∪ (a
→2 c)) = (a →2 c) |
| 11 | 10 | ax-r5 38 |
. . . . . . . . 9
(((a →2 c) ∪ (a
→2 c)) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) = ((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) |
| 12 | 9, 11 | ax-r2 36 |
. . . . . . . 8
((a →2 c) ∪ ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) = ((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) |
| 13 | | u2lemonb 636 |
. . . . . . . 8
((a →2 c) ∪ c⊥ ) = 1 |
| 14 | 12, 13 | 2an 79 |
. . . . . . 7
(((a →2 c) ∪ ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) ∩ ((a →2 c) ∪ c⊥ )) = (((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩
1) |
| 15 | 14 | ax-r1 35 |
. . . . . 6
(((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩ 1) =
(((a →2 c) ∪ ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) ∩ ((a →2 c) ∪ c⊥ )) |
| 16 | | an1 106 |
. . . . . . 7
(((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩ 1) =
((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) |
| 17 | 16 | ax-r1 35 |
. . . . . 6
((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) = (((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩
1) |
| 18 | | comorr 184 |
. . . . . . 7
(a →2 c) C ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) |
| 19 | | u2lemc1 681 |
. . . . . . . . 9
c C (a →2 c) |
| 20 | 19 | comcom 453 |
. . . . . . . 8
(a →2 c) C c |
| 21 | 20 | comcom2 183 |
. . . . . . 7
(a →2 c) C c⊥ |
| 22 | 18, 21 | fh3 471 |
. . . . . 6
((a →2 c) ∪ (((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩ c⊥ )) = (((a →2 c) ∪ ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) ∩ ((a →2 c) ∪ c⊥ )) |
| 23 | 15, 17, 22 | 3tr1 63 |
. . . . 5
((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) = ((a →2 c) ∪ (((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩ c⊥ )) |
| 24 | | oa23.1 |
. . . . . . . . 9
(c⊥ ∩
((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) ≤ a⊥ |
| 25 | | lea 160 |
. . . . . . . . 9
(c⊥ ∩
((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) ≤ c⊥ |
| 26 | 24, 25 | ler2an 173 |
. . . . . . . 8
(c⊥ ∩
((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) ≤ (a⊥ ∩ c⊥ ) |
| 27 | | ancom 74 |
. . . . . . . 8
(((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩ c⊥ ) = (c⊥ ∩ ((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b)))))) |
| 28 | | u2lemanb 616 |
. . . . . . . 8
((a →2 c) ∩ c⊥ ) = (a⊥ ∩ c⊥ ) |
| 29 | 26, 27, 28 | le3tr1 140 |
. . . . . . 7
(((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩ c⊥ ) ≤ ((a →2 c) ∩ c⊥ ) |
| 30 | 29 | lelor 166 |
. . . . . 6
((a →2 c) ∪ (((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩ c⊥ )) ≤ ((a →2 c) ∪ ((a
→2 c) ∩ c⊥ )) |
| 31 | | orabs 120 |
. . . . . 6
((a →2 c) ∪ ((a
→2 c) ∩ c⊥ )) = (a →2 c) |
| 32 | 30, 31 | lbtr 139 |
. . . . 5
((a →2 c) ∪ (((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ∩ c⊥ )) ≤ (a →2 c) |
| 33 | 23, 32 | bltr 138 |
. . . 4
((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) ≤ (a →2 c) |
| 34 | | leo 158 |
. . . 4
(a →2 c) ≤ ((a
→2 c) ∪ ((a →2 b) ∩ ((c
∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) |
| 35 | 33, 34 | lebi 145 |
. . 3
((a →2 c) ∪ ((a
→2 b) ∩ ((c ∪ b)⊥ ∪ ((a →2 c) ∩ (a
→2 b))))) = (a →2 c) |
| 36 | 6, 7, 35 | 3tr 65 |
. 2
(((a →2 b) ∩ ((b
∪ c)⊥ ∪ ((a →2 b) ∩ (a
→2 c)))) ∪ (a →2 c)) = (a
→2 c) |
| 37 | 36 | df-le1 130 |
1
((a →2 b) ∩ ((b
∪ c)⊥ ∪ ((a →2 b) ∩ (a
→2 c)))) ≤ (a →2 c) |