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Mirrors > Home > MPE Home > Th. List > bren | Structured version Visualization version GIF version |
Description: Equinumerosity relation. (Contributed by NM, 15-Jun-1998.) |
Ref | Expression |
---|---|
bren | ⊢ (𝐴 ≈ 𝐵 ↔ ∃𝑓 𝑓:𝐴–1-1-onto→𝐵) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | encv 8500 | . 2 ⊢ (𝐴 ≈ 𝐵 → (𝐴 ∈ V ∧ 𝐵 ∈ V)) | |
2 | f1ofn 6591 | . . . . 5 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝑓 Fn 𝐴) | |
3 | fndm 6425 | . . . . . 6 ⊢ (𝑓 Fn 𝐴 → dom 𝑓 = 𝐴) | |
4 | vex 3444 | . . . . . . 7 ⊢ 𝑓 ∈ V | |
5 | 4 | dmex 7598 | . . . . . 6 ⊢ dom 𝑓 ∈ V |
6 | 3, 5 | eqeltrrdi 2899 | . . . . 5 ⊢ (𝑓 Fn 𝐴 → 𝐴 ∈ V) |
7 | 2, 6 | syl 17 | . . . 4 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝐴 ∈ V) |
8 | f1ofo 6597 | . . . . . 6 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝑓:𝐴–onto→𝐵) | |
9 | forn 6568 | . . . . . 6 ⊢ (𝑓:𝐴–onto→𝐵 → ran 𝑓 = 𝐵) | |
10 | 8, 9 | syl 17 | . . . . 5 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → ran 𝑓 = 𝐵) |
11 | 4 | rnex 7599 | . . . . 5 ⊢ ran 𝑓 ∈ V |
12 | 10, 11 | eqeltrrdi 2899 | . . . 4 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → 𝐵 ∈ V) |
13 | 7, 12 | jca 515 | . . 3 ⊢ (𝑓:𝐴–1-1-onto→𝐵 → (𝐴 ∈ V ∧ 𝐵 ∈ V)) |
14 | 13 | exlimiv 1931 | . 2 ⊢ (∃𝑓 𝑓:𝐴–1-1-onto→𝐵 → (𝐴 ∈ V ∧ 𝐵 ∈ V)) |
15 | f1oeq2 6580 | . . . 4 ⊢ (𝑥 = 𝐴 → (𝑓:𝑥–1-1-onto→𝑦 ↔ 𝑓:𝐴–1-1-onto→𝑦)) | |
16 | 15 | exbidv 1922 | . . 3 ⊢ (𝑥 = 𝐴 → (∃𝑓 𝑓:𝑥–1-1-onto→𝑦 ↔ ∃𝑓 𝑓:𝐴–1-1-onto→𝑦)) |
17 | f1oeq3 6581 | . . . 4 ⊢ (𝑦 = 𝐵 → (𝑓:𝐴–1-1-onto→𝑦 ↔ 𝑓:𝐴–1-1-onto→𝐵)) | |
18 | 17 | exbidv 1922 | . . 3 ⊢ (𝑦 = 𝐵 → (∃𝑓 𝑓:𝐴–1-1-onto→𝑦 ↔ ∃𝑓 𝑓:𝐴–1-1-onto→𝐵)) |
19 | df-en 8493 | . . 3 ⊢ ≈ = {〈𝑥, 𝑦〉 ∣ ∃𝑓 𝑓:𝑥–1-1-onto→𝑦} | |
20 | 16, 18, 19 | brabg 5391 | . 2 ⊢ ((𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐴 ≈ 𝐵 ↔ ∃𝑓 𝑓:𝐴–1-1-onto→𝐵)) |
21 | 1, 14, 20 | pm5.21nii 383 | 1 ⊢ (𝐴 ≈ 𝐵 ↔ ∃𝑓 𝑓:𝐴–1-1-onto→𝐵) |
Colors of variables: wff setvar class |
Syntax hints: ↔ wb 209 ∧ wa 399 = wceq 1538 ∃wex 1781 ∈ wcel 2111 Vcvv 3441 class class class wbr 5030 dom cdm 5519 ran crn 5520 Fn wfn 6319 –onto→wfo 6322 –1-1-onto→wf1o 6323 ≈ cen 8489 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1797 ax-4 1811 ax-5 1911 ax-6 1970 ax-7 2015 ax-8 2113 ax-9 2121 ax-10 2142 ax-11 2158 ax-12 2175 ax-ext 2770 ax-sep 5167 ax-nul 5174 ax-pr 5295 ax-un 7441 |
This theorem depends on definitions: df-bi 210 df-an 400 df-or 845 df-3an 1086 df-tru 1541 df-ex 1782 df-nf 1786 df-sb 2070 df-mo 2598 df-eu 2629 df-clab 2777 df-cleq 2791 df-clel 2870 df-nfc 2938 df-ral 3111 df-rex 3112 df-rab 3115 df-v 3443 df-dif 3884 df-un 3886 df-in 3888 df-ss 3898 df-nul 4244 df-if 4426 df-sn 4526 df-pr 4528 df-op 4532 df-uni 4801 df-br 5031 df-opab 5093 df-xp 5525 df-rel 5526 df-cnv 5527 df-dm 5529 df-rn 5530 df-fn 6327 df-f 6328 df-f1 6329 df-fo 6330 df-f1o 6331 df-en 8493 |
This theorem is referenced by: domen 8505 f1oen3g 8508 ener 8539 en0 8555 ensn1 8556 en1 8559 unen 8579 enfixsn 8609 canth2 8654 mapen 8665 ssenen 8675 phplem4 8683 php3 8687 isinf 8715 ssfi 8722 domunfican 8775 fiint 8779 mapfien2 8856 unxpwdom2 9036 isinffi 9405 infxpenc2 9433 fseqen 9438 dfac8b 9442 infpwfien 9473 dfac12r 9557 infmap2 9629 cff1 9669 infpssr 9719 fin4en1 9720 enfin2i 9732 enfin1ai 9795 axcc3 9849 axcclem 9868 numth 9883 ttukey2g 9927 canthnum 10060 canthwe 10062 canthp1 10065 pwfseq 10075 tskuni 10194 gruen 10223 hasheqf1o 13705 hashfacen 13808 fz1f1o 15059 ruc 15588 cnso 15592 eulerth 16110 ablfaclem3 19202 lbslcic 20530 uvcendim 20536 indishmph 22403 ufldom 22567 ovolctb 24094 ovoliunlem3 24108 iunmbl2 24161 dyadmbl 24204 vitali 24217 cusgrfilem3 27247 padct 30481 f1ocnt 30551 volmeas 31600 eulerpart 31750 derangenlem 32531 mblfinlem1 35094 eldioph2lem1 39701 isnumbasgrplem1 40045 nnf1oxpnn 41823 sprsymrelen 44017 prproropen 44025 uspgrspren 44380 uspgrbisymrel 44382 1aryenef 45059 2aryenef 45070 rrx2xpreen 45133 |
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