Proof of Theorem oago3.21x
| Step | Hyp | Ref
| Expression |
| 1 | | i5lei1 347 |
. . . . . 6
(a →5 b) ≤ (a
→1 b) |
| 2 | | i5lei2 348 |
. . . . . 6
(b →5 c) ≤ (b
→2 c) |
| 3 | 1, 2 | le2an 169 |
. . . . 5
((a →5 b) ∩ (b
→5 c)) ≤ ((a →1 b) ∩ (b
→2 c)) |
| 4 | | i5lei1 347 |
. . . . 5
(c →5 d) ≤ (c
→1 d) |
| 5 | 3, 4 | le2an 169 |
. . . 4
(((a →5 b) ∩ (b
→5 c)) ∩ (c →5 d)) ≤ (((a
→1 b) ∩ (b →2 c)) ∩ (c
→1 d)) |
| 6 | | i5lei2 348 |
. . . 4
(d →5 a) ≤ (d
→2 a) |
| 7 | 5, 6 | le2an 169 |
. . 3
((((a →5 b) ∩ (b
→5 c)) ∩ (c →5 d)) ∩ (d
→5 a)) ≤ ((((a →1 b) ∩ (b
→2 c)) ∩ (c →1 d)) ∩ (d
→2 a)) |
| 8 | | mhcor1 888 |
. . 3
((((a →1 b) ∩ (b
→2 c)) ∩ (c →1 d)) ∩ (d
→2 a)) = (((a ≡ b)
∩ (b ≡ c)) ∩ (c
≡ d)) |
| 9 | 7, 8 | lbtr 139 |
. 2
((((a →5 b) ∩ (b
→5 c)) ∩ (c →5 d)) ∩ (d
→5 a)) ≤ (((a ≡ b)
∩ (b ≡ c)) ∩ (c
≡ d)) |
| 10 | | leid 148 |
. . . 4
(((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d))
≤ (((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d)) |
| 11 | | eqtr4 834 |
. . . . 5
(((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d))
≤ (a ≡ d) |
| 12 | | bicom 96 |
. . . . 5
(a ≡ d) = (d ≡
a) |
| 13 | 11, 12 | lbtr 139 |
. . . 4
(((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d))
≤ (d ≡ a) |
| 14 | 10, 13 | ler2an 173 |
. . 3
(((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d))
≤ ((((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d))
∩ (d ≡ a)) |
| 15 | | u5lembi 725 |
. . . . . . . 8
((a →5 b) ∩ (b
→5 a)) = (a ≡ b) |
| 16 | 15 | ax-r1 35 |
. . . . . . 7
(a ≡ b) = ((a
→5 b) ∩ (b →5 a)) |
| 17 | | lea 160 |
. . . . . . 7
((a →5 b) ∩ (b
→5 a)) ≤ (a →5 b) |
| 18 | 16, 17 | bltr 138 |
. . . . . 6
(a ≡ b) ≤ (a
→5 b) |
| 19 | | u5lembi 725 |
. . . . . . . 8
((b →5 c) ∩ (c
→5 b)) = (b ≡ c) |
| 20 | 19 | ax-r1 35 |
. . . . . . 7
(b ≡ c) = ((b
→5 c) ∩ (c →5 b)) |
| 21 | | lea 160 |
. . . . . . 7
((b →5 c) ∩ (c
→5 b)) ≤ (b →5 c) |
| 22 | 20, 21 | bltr 138 |
. . . . . 6
(b ≡ c) ≤ (b
→5 c) |
| 23 | 18, 22 | le2an 169 |
. . . . 5
((a ≡ b) ∩ (b
≡ c)) ≤ ((a →5 b) ∩ (b
→5 c)) |
| 24 | | u5lembi 725 |
. . . . . . 7
((c →5 d) ∩ (d
→5 c)) = (c ≡ d) |
| 25 | 24 | ax-r1 35 |
. . . . . 6
(c ≡ d) = ((c
→5 d) ∩ (d →5 c)) |
| 26 | | lea 160 |
. . . . . 6
((c →5 d) ∩ (d
→5 c)) ≤ (c →5 d) |
| 27 | 25, 26 | bltr 138 |
. . . . 5
(c ≡ d) ≤ (c
→5 d) |
| 28 | 23, 27 | le2an 169 |
. . . 4
(((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d))
≤ (((a →5 b) ∩ (b
→5 c)) ∩ (c →5 d)) |
| 29 | | u5lembi 725 |
. . . . . 6
((d →5 a) ∩ (a
→5 d)) = (d ≡ a) |
| 30 | 29 | ax-r1 35 |
. . . . 5
(d ≡ a) = ((d
→5 a) ∩ (a →5 d)) |
| 31 | | lea 160 |
. . . . 5
((d →5 a) ∩ (a
→5 d)) ≤ (d →5 a) |
| 32 | 30, 31 | bltr 138 |
. . . 4
(d ≡ a) ≤ (d
→5 a) |
| 33 | 28, 32 | le2an 169 |
. . 3
((((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d))
∩ (d ≡ a)) ≤ ((((a
→5 b) ∩ (b →5 c)) ∩ (c
→5 d)) ∩ (d →5 a)) |
| 34 | 14, 33 | letr 137 |
. 2
(((a ≡ b) ∩ (b
≡ c)) ∩ (c ≡ d))
≤ ((((a →5 b) ∩ (b
→5 c)) ∩ (c →5 d)) ∩ (d
→5 a)) |
| 35 | 9, 34 | lebi 145 |
1
((((a →5 b) ∩ (b
→5 c)) ∩ (c →5 d)) ∩ (d
→5 a)) = (((a ≡ b)
∩ (b ≡ c)) ∩ (c
≡ d)) |