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Theorem feq123d 5426
Description: Equality deduction for functions. (Contributed by Paul Chapman, 22-Jun-2011.)
Hypotheses
Ref Expression
feq12d.1  |-  ( ph  ->  F  =  G )
feq12d.2  |-  ( ph  ->  A  =  B )
feq123d.3  |-  ( ph  ->  C  =  D )
Assertion
Ref Expression
feq123d  |-  ( ph  ->  ( F : A --> C 
<->  G : B --> D ) )

Proof of Theorem feq123d
StepHypRef Expression
1 feq12d.1 . . 3  |-  ( ph  ->  F  =  G )
2 feq12d.2 . . 3  |-  ( ph  ->  A  =  B )
31, 2feq12d 5425 . 2  |-  ( ph  ->  ( F : A --> C 
<->  G : B --> C ) )
4 feq123d.3 . . 3  |-  ( ph  ->  C  =  D )
5 feq3 5420 . . 3  |-  ( C  =  D  ->  ( G : B --> C  <->  G : B
--> D ) )
64, 5syl 14 . 2  |-  ( ph  ->  ( G : B --> C 
<->  G : B --> D ) )
73, 6bitrd 188 1  |-  ( ph  ->  ( F : A --> C 
<->  G : B --> D ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 105    = wceq 1373   -->wf 5276
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-ext 2188
This theorem depends on definitions:  df-bi 117  df-3an 983  df-tru 1376  df-nf 1485  df-sb 1787  df-clab 2193  df-cleq 2199  df-clel 2202  df-nfc 2338  df-v 2775  df-un 3174  df-in 3176  df-ss 3183  df-sn 3644  df-pr 3645  df-op 3647  df-br 4052  df-opab 4114  df-rel 4690  df-cnv 4691  df-co 4692  df-dm 4693  df-rn 4694  df-fun 5282  df-fn 5283  df-f 5284
This theorem is referenced by:  feq123  5427  feq23d  5431  csbwrdg  11045  isuhgrm  15742  uhgreq12g  15747  isuhgropm  15752  uhgrun  15757  isupgren  15766  upgrop  15775  isumgren  15776  upgrun  15792  umgrun  15794
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