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Mirrors > Home > MPE Home > Th. List > Mathboxes > oninfint | Structured version Visualization version GIF version |
Description: The infimum of a non-empty class of ordinals is the intersection of that class. (Contributed by RP, 23-Jan-2025.) |
Ref | Expression |
---|---|
oninfint | ⊢ ((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) → inf(𝐴, On, E ) = ∩ 𝐴) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | epweon 7759 | . . 3 ⊢ E We On | |
2 | weso 5660 | . . 3 ⊢ ( E We On → E Or On) | |
3 | 1, 2 | mp1i 13 | . 2 ⊢ ((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) → E Or On) |
4 | oninton 7780 | . 2 ⊢ ((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) → ∩ 𝐴 ∈ On) | |
5 | onint 7775 | . 2 ⊢ ((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) → ∩ 𝐴 ∈ 𝐴) | |
6 | intss1 4960 | . . . . 5 ⊢ (𝑥 ∈ 𝐴 → ∩ 𝐴 ⊆ 𝑥) | |
7 | 6 | adantl 481 | . . . 4 ⊢ (((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) ∧ 𝑥 ∈ 𝐴) → ∩ 𝐴 ⊆ 𝑥) |
8 | simpl 482 | . . . . . 6 ⊢ ((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) → 𝐴 ⊆ On) | |
9 | 8 | sselda 3977 | . . . . 5 ⊢ (((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) ∧ 𝑥 ∈ 𝐴) → 𝑥 ∈ On) |
10 | ontri1 6392 | . . . . 5 ⊢ ((∩ 𝐴 ∈ On ∧ 𝑥 ∈ On) → (∩ 𝐴 ⊆ 𝑥 ↔ ¬ 𝑥 ∈ ∩ 𝐴)) | |
11 | 4, 9, 10 | syl2an2r 682 | . . . 4 ⊢ (((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) ∧ 𝑥 ∈ 𝐴) → (∩ 𝐴 ⊆ 𝑥 ↔ ¬ 𝑥 ∈ ∩ 𝐴)) |
12 | 7, 11 | mpbid 231 | . . 3 ⊢ (((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) ∧ 𝑥 ∈ 𝐴) → ¬ 𝑥 ∈ ∩ 𝐴) |
13 | epelg 5574 | . . . . 5 ⊢ (∩ 𝐴 ∈ On → (𝑥 E ∩ 𝐴 ↔ 𝑥 ∈ ∩ 𝐴)) | |
14 | 4, 13 | syl 17 | . . . 4 ⊢ ((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) → (𝑥 E ∩ 𝐴 ↔ 𝑥 ∈ ∩ 𝐴)) |
15 | 14 | adantr 480 | . . 3 ⊢ (((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) ∧ 𝑥 ∈ 𝐴) → (𝑥 E ∩ 𝐴 ↔ 𝑥 ∈ ∩ 𝐴)) |
16 | 12, 15 | mtbird 325 | . 2 ⊢ (((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) ∧ 𝑥 ∈ 𝐴) → ¬ 𝑥 E ∩ 𝐴) |
17 | 3, 4, 5, 16 | infmin 9491 | 1 ⊢ ((𝐴 ⊆ On ∧ 𝐴 ≠ ∅) → inf(𝐴, On, E ) = ∩ 𝐴) |
Colors of variables: wff setvar class |
Syntax hints: ¬ wn 3 → wi 4 ↔ wb 205 ∧ wa 395 = wceq 1533 ∈ wcel 2098 ≠ wne 2934 ⊆ wss 3943 ∅c0 4317 ∩ cint 4943 class class class wbr 5141 E cep 5572 Or wor 5580 We wwe 5623 Oncon0 6358 infcinf 9438 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1789 ax-4 1803 ax-5 1905 ax-6 1963 ax-7 2003 ax-8 2100 ax-9 2108 ax-10 2129 ax-11 2146 ax-12 2163 ax-ext 2697 ax-sep 5292 ax-nul 5299 ax-pr 5420 |
This theorem depends on definitions: df-bi 206 df-an 396 df-or 845 df-3or 1085 df-3an 1086 df-tru 1536 df-fal 1546 df-ex 1774 df-nf 1778 df-sb 2060 df-mo 2528 df-eu 2557 df-clab 2704 df-cleq 2718 df-clel 2804 df-nfc 2879 df-ne 2935 df-ral 3056 df-rex 3065 df-rmo 3370 df-reu 3371 df-rab 3427 df-v 3470 df-dif 3946 df-un 3948 df-in 3950 df-ss 3960 df-pss 3962 df-nul 4318 df-if 4524 df-pw 4599 df-sn 4624 df-pr 4626 df-op 4630 df-uni 4903 df-int 4944 df-br 5142 df-opab 5204 df-tr 5259 df-eprel 5573 df-po 5581 df-so 5582 df-fr 5624 df-we 5626 df-cnv 5677 df-ord 6361 df-on 6362 df-iota 6489 df-riota 7361 df-sup 9439 df-inf 9440 |
This theorem is referenced by: oninfunirab 42562 |
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