Proof of Theorem gomaex3lem2
| Step | Hyp | Ref
| Expression |
| 1 | | gomaex3lem2.5 |
. . . . . 6
e ≤ f⊥ |
| 2 | 1 | lecon3 149 |
. . . . 5
f ≤ e⊥ |
| 3 | 2 | lecom 172 |
. . . 4
f C e⊥ |
| 4 | | comid 179 |
. . . . 5
f C f |
| 5 | 4 | comcom2 175 |
. . . 4
f C f⊥ |
| 6 | 3, 5 | fh3r 457 |
. . 3
((e⊥ ∩ f⊥ ) ∪ f) = ((e⊥ ∪ f) ∩ (f⊥ ∪ f)) |
| 7 | | anor3 82 |
. . . . 5
(e⊥ ∩ f⊥ ) = (e ∪ f)⊥ |
| 8 | 7 | ax-r5 37 |
. . . 4
((e⊥ ∩ f⊥ ) ∪ f) = ((e ∪
f)⊥ ∪ f) |
| 9 | 8 | ax-r1 34 |
. . 3
((e ∪ f)⊥ ∪ f) = ((e⊥ ∩ f⊥ ) ∪ f) |
| 10 | | a5c 113 |
. . . . . 6
(e⊥ ∩ (e⊥ ∪ f)) = e⊥ |
| 11 | 10 | df2le1 127 |
. . . . 5
e⊥ ≤ (e⊥ ∪ f) |
| 12 | | leid 140 |
. . . . . 6
e⊥ ≤ e⊥ |
| 13 | 12, 2 | lel2or 162 |
. . . . 5
(e⊥ ∪ f) ≤ e⊥ |
| 14 | 11, 13 | lebi 137 |
. . . 4
e⊥ = (e⊥ ∪ f) |
| 15 | | df-t 40 |
. . . . 5
1 = (f ∪ f⊥ ) |
| 16 | | ax-a2 30 |
. . . . 5
(f ∪ f⊥ ) = (f⊥ ∪ f) |
| 17 | 15, 16 | ax-r2 35 |
. . . 4
1 = (f⊥ ∪ f) |
| 18 | 14, 17 | 2an 72 |
. . 3
(e⊥ ∩ 1) = ((e⊥ ∪ f) ∩ (f⊥ ∪ f)) |
| 19 | 6, 9, 18 | 3tr1 60 |
. 2
((e ∪ f)⊥ ∪ f) = (e⊥ ∩ 1) |
| 20 | | an1 98 |
. 2
(e⊥ ∩ 1) = e⊥ |
| 21 | 19, 20 | ax-r2 35 |
1
((e ∪ f)⊥ ∪ f) = e⊥ |