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Mirrors > Home > ILE Home > Th. List > dfer2 | Unicode version |
Description: Alternate definition of equivalence predicate. (Contributed by NM, 3-Jan-1997.) (Revised by Mario Carneiro, 12-Aug-2015.) |
Ref | Expression |
---|---|
dfer2 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | df-er 6106 | . 2 | |
2 | cnvsym 4708 | . . . . 5 | |
3 | cotr 4706 | . . . . 5 | |
4 | 2, 3 | anbi12i 433 | . . . 4 |
5 | unss 3117 | . . . 4 | |
6 | 19.28v 1780 | . . . . . . . 8 | |
7 | 6 | albii 1359 | . . . . . . 7 |
8 | 19.26 1370 | . . . . . . 7 | |
9 | 7, 8 | bitri 173 | . . . . . 6 |
10 | 9 | albii 1359 | . . . . 5 |
11 | 19.26 1370 | . . . . 5 | |
12 | 10, 11 | bitr2i 174 | . . . 4 |
13 | 4, 5, 12 | 3bitr3i 199 | . . 3 |
14 | 13 | 3anbi3i 1097 | . 2 |
15 | 1, 14 | bitri 173 | 1 |
Colors of variables: wff set class |
Syntax hints: wi 4 wa 97 wb 98 w3a 885 wal 1241 wceq 1243 cun 2915 wss 2917 class class class wbr 3764 ccnv 4344 cdm 4345 ccom 4349 wrel 4350 wer 6103 |
This theorem was proved from axioms: ax-1 5 ax-2 6 ax-mp 7 ax-ia1 99 ax-ia2 100 ax-ia3 101 ax-io 630 ax-5 1336 ax-7 1337 ax-gen 1338 ax-ie1 1382 ax-ie2 1383 ax-8 1395 ax-10 1396 ax-11 1397 ax-i12 1398 ax-bndl 1399 ax-4 1400 ax-14 1405 ax-17 1419 ax-i9 1423 ax-ial 1427 ax-i5r 1428 ax-ext 2022 ax-sep 3875 ax-pow 3927 ax-pr 3944 |
This theorem depends on definitions: df-bi 110 df-3an 887 df-tru 1246 df-nf 1350 df-sb 1646 df-eu 1903 df-mo 1904 df-clab 2027 df-cleq 2033 df-clel 2036 df-nfc 2167 df-ral 2311 df-rex 2312 df-v 2559 df-un 2922 df-in 2924 df-ss 2931 df-pw 3361 df-sn 3381 df-pr 3382 df-op 3384 df-br 3765 df-opab 3819 df-xp 4351 df-rel 4352 df-cnv 4353 df-co 4354 df-er 6106 |
This theorem is referenced by: iserd 6132 |
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