Proof of Theorem oadistc
| Step | Hyp | Ref
| Expression |
| 1 | | oadistc.2 |
. . 3
((a →2 b) ∩ ((b
∪ c)⊥ ∪ d)) ≤ (((a
→2 b) ∩ (b ∪ c)⊥ ) ∪ d) |
| 2 | | oadistc.1 |
. . . . . . . 8
d ≤ ((a →2 b) ∩ (a
→2 c)) |
| 3 | | lea 152 |
. . . . . . . 8
((a →2 b) ∩ (a
→2 c)) ≤ (a →2 b) |
| 4 | 2, 3 | letr 129 |
. . . . . . 7
d ≤ (a →2 b) |
| 5 | 4 | df2le2 128 |
. . . . . 6
(d ∩ (a →2 b)) = d |
| 6 | 5 | ax-r1 34 |
. . . . 5
d = (d
∩ (a →2 b)) |
| 7 | | ancom 68 |
. . . . 5
(d ∩ (a →2 b)) = ((a
→2 b) ∩ d) |
| 8 | 6, 7 | ax-r2 35 |
. . . 4
d = ((a
→2 b) ∩ d) |
| 9 | 8 | lor 66 |
. . 3
(((a →2 b) ∩ (b
∪ c)⊥ ) ∪ d) = (((a
→2 b) ∩ (b ∪ c)⊥ ) ∪ ((a →2 b) ∩ d)) |
| 10 | 1, 9 | lbtr 131 |
. 2
((a →2 b) ∩ ((b
∪ c)⊥ ∪ d)) ≤ (((a
→2 b) ∩ (b ∪ c)⊥ ) ∪ ((a →2 b) ∩ d)) |
| 11 | | ledi 166 |
. 2
(((a →2 b) ∩ (b
∪ c)⊥ ) ∪
((a →2 b) ∩ d))
≤ ((a →2 b) ∩ ((b
∪ c)⊥ ∪ d)) |
| 12 | 10, 11 | lebi 137 |
1
((a →2 b) ∩ ((b
∪ c)⊥ ∪ d)) = (((a
→2 b) ∩ (b ∪ c)⊥ ) ∪ ((a →2 b) ∩ d)) |