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Theorem funeq 4847
Description: Equality theorem for function predicate. (Contributed by NM, 16-Aug-1994.)
Assertion
Ref Expression
funeq (A = B → (Fun A ↔ Fun B))

Proof of Theorem funeq
StepHypRef Expression
1 eqimss2 2975 . . 3 (A = BBA)
2 funss 4846 . . 3 (BA → (Fun A → Fun B))
31, 2syl 14 . 2 (A = B → (Fun A → Fun B))
4 eqimss 2974 . . 3 (A = BAB)
5 funss 4846 . . 3 (AB → (Fun B → Fun A))
64, 5syl 14 . 2 (A = B → (Fun B → Fun A))
73, 6impbid 120 1 (A = B → (Fun A ↔ Fun B))
Colors of variables: wff set class
Syntax hints:  wi 4  wb 98   = wceq 1228  wss 2894  Fun wfun 4823
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 617  ax-5 1316  ax-7 1317  ax-gen 1318  ax-ie1 1363  ax-ie2 1364  ax-8 1376  ax-10 1377  ax-11 1378  ax-i12 1379  ax-bnd 1380  ax-4 1381  ax-17 1400  ax-i9 1404  ax-ial 1409  ax-i5r 1410  ax-ext 2004
This theorem depends on definitions:  df-bi 110  df-nf 1330  df-sb 1628  df-clab 2009  df-cleq 2015  df-clel 2018  df-nfc 2149  df-in 2901  df-ss 2908  df-br 3739  df-opab 3793  df-rel 4279  df-cnv 4280  df-co 4281  df-fun 4831
This theorem is referenced by:  funeqi  4848  funeqd  4849  fununi  4893  funcnvuni  4894  cnvresid  4899  fneq1  4913
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