Proof of Theorem relcnvtrg
Step | Hyp | Ref
| Expression |
1 | | cnvco 5783 |
. . 3
⊢ ◡(𝑅 ∘ 𝑆) = (◡𝑆 ∘ ◡𝑅) |
2 | | cnvss 5770 |
. . 3
⊢ ((𝑅 ∘ 𝑆) ⊆ 𝑇 → ◡(𝑅 ∘ 𝑆) ⊆ ◡𝑇) |
3 | 1, 2 | eqsstrrid 3966 |
. 2
⊢ ((𝑅 ∘ 𝑆) ⊆ 𝑇 → (◡𝑆 ∘ ◡𝑅) ⊆ ◡𝑇) |
4 | | cnvco 5783 |
. . . 4
⊢ ◡(◡𝑆 ∘ ◡𝑅) = (◡◡𝑅 ∘ ◡◡𝑆) |
5 | | cnvss 5770 |
. . . 4
⊢ ((◡𝑆 ∘ ◡𝑅) ⊆ ◡𝑇 → ◡(◡𝑆 ∘ ◡𝑅) ⊆ ◡◡𝑇) |
6 | | sseq1 3942 |
. . . . 5
⊢ (◡(◡𝑆 ∘ ◡𝑅) = (◡◡𝑅 ∘ ◡◡𝑆) → (◡(◡𝑆 ∘ ◡𝑅) ⊆ ◡◡𝑇 ↔ (◡◡𝑅 ∘ ◡◡𝑆) ⊆ ◡◡𝑇)) |
7 | | dfrel2 6081 |
. . . . . . . . . 10
⊢ (Rel
𝑅 ↔ ◡◡𝑅 = 𝑅) |
8 | 7 | biimpi 215 |
. . . . . . . . 9
⊢ (Rel
𝑅 → ◡◡𝑅 = 𝑅) |
9 | 8 | 3ad2ant1 1131 |
. . . . . . . 8
⊢ ((Rel
𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → ◡◡𝑅 = 𝑅) |
10 | | dfrel2 6081 |
. . . . . . . . . 10
⊢ (Rel
𝑆 ↔ ◡◡𝑆 = 𝑆) |
11 | 10 | biimpi 215 |
. . . . . . . . 9
⊢ (Rel
𝑆 → ◡◡𝑆 = 𝑆) |
12 | 11 | 3ad2ant2 1132 |
. . . . . . . 8
⊢ ((Rel
𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → ◡◡𝑆 = 𝑆) |
13 | 9, 12 | coeq12d 5762 |
. . . . . . 7
⊢ ((Rel
𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → (◡◡𝑅 ∘ ◡◡𝑆) = (𝑅 ∘ 𝑆)) |
14 | | dfrel2 6081 |
. . . . . . . . 9
⊢ (Rel
𝑇 ↔ ◡◡𝑇 = 𝑇) |
15 | 14 | biimpi 215 |
. . . . . . . 8
⊢ (Rel
𝑇 → ◡◡𝑇 = 𝑇) |
16 | 15 | 3ad2ant3 1133 |
. . . . . . 7
⊢ ((Rel
𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → ◡◡𝑇 = 𝑇) |
17 | 13, 16 | sseq12d 3950 |
. . . . . 6
⊢ ((Rel
𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → ((◡◡𝑅 ∘ ◡◡𝑆) ⊆ ◡◡𝑇 ↔ (𝑅 ∘ 𝑆) ⊆ 𝑇)) |
18 | 17 | biimpcd 248 |
. . . . 5
⊢ ((◡◡𝑅 ∘ ◡◡𝑆) ⊆ ◡◡𝑇 → ((Rel 𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → (𝑅 ∘ 𝑆) ⊆ 𝑇)) |
19 | 6, 18 | syl6bi 252 |
. . . 4
⊢ (◡(◡𝑆 ∘ ◡𝑅) = (◡◡𝑅 ∘ ◡◡𝑆) → (◡(◡𝑆 ∘ ◡𝑅) ⊆ ◡◡𝑇 → ((Rel 𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → (𝑅 ∘ 𝑆) ⊆ 𝑇))) |
20 | 4, 5, 19 | mpsyl 68 |
. . 3
⊢ ((◡𝑆 ∘ ◡𝑅) ⊆ ◡𝑇 → ((Rel 𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → (𝑅 ∘ 𝑆) ⊆ 𝑇)) |
21 | 20 | com12 32 |
. 2
⊢ ((Rel
𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → ((◡𝑆 ∘ ◡𝑅) ⊆ ◡𝑇 → (𝑅 ∘ 𝑆) ⊆ 𝑇)) |
22 | 3, 21 | impbid2 225 |
1
⊢ ((Rel
𝑅 ∧ Rel 𝑆 ∧ Rel 𝑇) → ((𝑅 ∘ 𝑆) ⊆ 𝑇 ↔ (◡𝑆 ∘ ◡𝑅) ⊆ ◡𝑇)) |