Proof of Theorem marsdenlem4
| Step | Hyp | Ref
| Expression |
| 1 | | leao3 156 |
. . . . . 6
(b⊥ ∩ d) ≤ (a ∪
b⊥ ) |
| 2 | | oran1 83 |
. . . . . 6
(a ∪ b⊥ ) = (a⊥ ∩ b)⊥ |
| 3 | 1, 2 | lbtr 131 |
. . . . 5
(b⊥ ∩ d) ≤ (a⊥ ∩ b)⊥ |
| 4 | 3 | lecom 172 |
. . . 4
(b⊥ ∩ d) C (a⊥ ∩ b)⊥ |
| 5 | 4 | comcom7 442 |
. . 3
(b⊥ ∩ d) C (a⊥ ∩ b) |
| 6 | | leao4 157 |
. . . . . 6
(b⊥ ∩ d) ≤ (a⊥ ∪ d) |
| 7 | | oran2 84 |
. . . . . 6
(a⊥ ∪ d) = (a ∩
d⊥
)⊥ |
| 8 | 6, 7 | lbtr 131 |
. . . . 5
(b⊥ ∩ d) ≤ (a ∩
d⊥
)⊥ |
| 9 | 8 | lecom 172 |
. . . 4
(b⊥ ∩ d) C (a
∩ d⊥
)⊥ |
| 10 | 9 | comcom7 442 |
. . 3
(b⊥ ∩ d) C (a
∩ d⊥ ) |
| 11 | 5, 10 | fh1r 455 |
. 2
(((a⊥ ∩ b) ∪ (a
∩ d⊥ )) ∩
(b⊥ ∩ d)) = (((a⊥ ∩ b) ∩ (b⊥ ∩ d)) ∪ ((a
∩ d⊥ ) ∩ (b⊥ ∩ d))) |
| 12 | | ancom 68 |
. . . . 5
(b⊥ ∩ d) = (d ∩
b⊥ ) |
| 13 | 12 | lan 70 |
. . . 4
((a⊥ ∩ b) ∩ (b⊥ ∩ d)) = ((a⊥ ∩ b) ∩ (d
∩ b⊥ )) |
| 14 | | an4 78 |
. . . 4
((a⊥ ∩ b) ∩ (d
∩ b⊥ )) = ((a⊥ ∩ d) ∩ (b
∩ b⊥ )) |
| 15 | | dff 93 |
. . . . . . 7
0 = (b ∩ b⊥ ) |
| 16 | 15 | lan 70 |
. . . . . 6
((a⊥ ∩ d) ∩ 0) = ((a⊥ ∩ d) ∩ (b
∩ b⊥ )) |
| 17 | 16 | ax-r1 34 |
. . . . 5
((a⊥ ∩ d) ∩ (b
∩ b⊥ )) = ((a⊥ ∩ d) ∩ 0) |
| 18 | | an0 100 |
. . . . 5
((a⊥ ∩ d) ∩ 0) = 0 |
| 19 | 17, 18 | ax-r2 35 |
. . . 4
((a⊥ ∩ d) ∩ (b
∩ b⊥ )) = 0 |
| 20 | 13, 14, 19 | 3tr 62 |
. . 3
((a⊥ ∩ b) ∩ (b⊥ ∩ d)) = 0 |
| 21 | | an4 78 |
. . . 4
((a ∩ d⊥ ) ∩ (b⊥ ∩ d)) = ((a ∩
b⊥ ) ∩ (d⊥ ∩ d)) |
| 22 | | ancom 68 |
. . . . . 6
(d⊥ ∩ d) = (d ∩
d⊥ ) |
| 23 | | dff 93 |
. . . . . . 7
0 = (d ∩ d⊥ ) |
| 24 | 23 | ax-r1 34 |
. . . . . 6
(d ∩ d⊥ ) = 0 |
| 25 | 22, 24 | ax-r2 35 |
. . . . 5
(d⊥ ∩ d) = 0 |
| 26 | 25 | lan 70 |
. . . 4
((a ∩ b⊥ ) ∩ (d⊥ ∩ d)) = ((a ∩
b⊥ ) ∩ 0) |
| 27 | | an0 100 |
. . . 4
((a ∩ b⊥ ) ∩ 0) = 0 |
| 28 | 21, 26, 27 | 3tr 62 |
. . 3
((a ∩ d⊥ ) ∩ (b⊥ ∩ d)) = 0 |
| 29 | 20, 28 | 2or 67 |
. 2
(((a⊥ ∩ b) ∩ (b⊥ ∩ d)) ∪ ((a
∩ d⊥ ) ∩ (b⊥ ∩ d))) = (0 ∪ 0) |
| 30 | | or0 94 |
. 2
(0 ∪ 0) = 0 |
| 31 | 11, 29, 30 | 3tr 62 |
1
(((a⊥ ∩ b) ∪ (a
∩ d⊥ )) ∩
(b⊥ ∩ d)) = 0 |