Theorem feq23d 5268

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 2140	. 2 |- ( ph -> F = F )
2		feq23d.1	. 2 |- ( ph -> A = C )
3		feq23d.2	. 2 |- ( ph -> B = D )
4	1, 2, 3	feq123d 5263	1 |- ( ph -> ( F : A --> B <-> F : C --> D ) )

Syntax hints:   -> wi 4   <-> wb 104   = wceq 1331   -->wf 5119

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-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2121

This theorem depends on definitions:  df-bi 116  df-3an 964  df-tru 1334  df-nf 1437  df-sb 1736  df-clab 2126  df-cleq 2132  df-clel 2135  df-nfc 2270  df-v 2688  df-un 3075  df-in 3077  df-ss 3084  df-sn 3533  df-pr 3534  df-op 3536  df-br 3930  df-opab 3990  df-rel 4546  df-cnv 4547  df-co 4548  df-dm 4549  df-rn 4550  df-fun 5125  df-fn 5126  df-f 5127

This theorem is referenced by: (None)