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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 6422 | . 2 | |
2 | cnvsym 4917 | . . . . 5 | |
3 | cotr 4915 | . . . . 5 | |
4 | 2, 3 | anbi12i 455 | . . . 4 |
5 | unss 3245 | . . . 4 | |
6 | 19.28v 1872 | . . . . . . . 8 | |
7 | 6 | albii 1446 | . . . . . . 7 |
8 | 19.26 1457 | . . . . . . 7 | |
9 | 7, 8 | bitri 183 | . . . . . 6 |
10 | 9 | albii 1446 | . . . . 5 |
11 | 19.26 1457 | . . . . 5 | |
12 | 10, 11 | bitr2i 184 | . . . 4 |
13 | 4, 5, 12 | 3bitr3i 209 | . . 3 |
14 | 13 | 3anbi3i 1174 | . 2 |
15 | 1, 14 | bitri 183 | 1 |
Colors of variables: wff set class |
Syntax hints: wi 4 wa 103 wb 104 w3a 962 wal 1329 wceq 1331 cun 3064 wss 3066 class class class wbr 3924 ccnv 4533 cdm 4534 ccom 4538 wrel 4539 wer 6419 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 105 ax-ia2 106 ax-ia3 107 ax-io 698 ax-5 1423 ax-7 1424 ax-gen 1425 ax-ie1 1469 ax-ie2 1470 ax-8 1482 ax-10 1483 ax-11 1484 ax-i12 1485 ax-bndl 1486 ax-4 1487 ax-14 1492 ax-17 1506 ax-i9 1510 ax-ial 1514 ax-i5r 1515 ax-ext 2119 ax-sep 4041 ax-pow 4093 ax-pr 4126 |
This theorem depends on definitions: df-bi 116 df-3an 964 df-tru 1334 df-nf 1437 df-sb 1736 df-eu 2000 df-mo 2001 df-clab 2124 df-cleq 2130 df-clel 2133 df-nfc 2268 df-ral 2419 df-rex 2420 df-v 2683 df-un 3070 df-in 3072 df-ss 3079 df-pw 3507 df-sn 3528 df-pr 3529 df-op 3531 df-br 3925 df-opab 3985 df-xp 4540 df-rel 4541 df-cnv 4542 df-co 4543 df-er 6422 |
This theorem is referenced by: iserd 6448 |
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