Theorem feq23d 5276

Description: Equality deduction for functions. (Contributed by NM, 8-Jun-2013.)

Hypotheses

Ref	Expression
feq23d.1	|- ( ph -> A = C )
feq23d.2	|- ( ph -> B = D )

Assertion

Ref	Expression
feq23d	|- ( ph -> ( F : A --> B <-> F : C --> D ) )

Proof of Theorem feq23d

Step	Hyp	Ref	Expression
1		eqidd 2141	. 2 |- ( ph -> F = F )
2		feq23d.1	. 2 |- ( ph -> A = C )
3		feq23d.2	. 2 |- ( ph -> B = D )
4	1, 2, 3	feq123d 5271	1 |- ( ph -> ( F : A --> B <-> F : C --> D ) )

Syntax hints:   -> wi 4   <-> wb 104   = wceq 1332   -->wf 5127

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 699  ax-5 1424  ax-7 1425  ax-gen 1426  ax-ie1 1470  ax-ie2 1471  ax-8 1483  ax-10 1484  ax-11 1485  ax-i12 1486  ax-bndl 1487  ax-4 1488  ax-17 1507  ax-i9 1511  ax-ial 1515  ax-i5r 1516  ax-ext 2122

This theorem depends on definitions:  df-bi 116  df-3an 965  df-tru 1335  df-nf 1438  df-sb 1737  df-clab 2127  df-cleq 2133  df-clel 2136  df-nfc 2271  df-v 2691  df-un 3080  df-in 3082  df-ss 3089  df-sn 3538  df-pr 3539  df-op 3541  df-br 3938  df-opab 3998  df-rel 4554  df-cnv 4555  df-co 4556  df-dm 4557  df-rn 4558  df-fun 5133  df-fn 5134  df-f 5135

This theorem is referenced by: (None)