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Theorem feq123d 5524
Description: Equality deduction for functions. (Contributed by Paul Chapman, 22-Jun-2011.)
Hypotheses
Ref Expression
feq12d.1 (𝜑𝐹 = 𝐺)
feq12d.2 (𝜑𝐴 = 𝐵)
feq123d.3 (𝜑𝐶 = 𝐷)
Assertion
Ref Expression
feq123d (𝜑 → (𝐹:𝐴𝐶𝐺:𝐵𝐷))

Proof of Theorem feq123d
StepHypRef Expression
1 feq12d.1 . . 3 (𝜑𝐹 = 𝐺)
2 feq12d.2 . . 3 (𝜑𝐴 = 𝐵)
31, 2feq12d 5523 . 2 (𝜑 → (𝐹:𝐴𝐶𝐺:𝐵𝐶))
4 feq123d.3 . . 3 (𝜑𝐶 = 𝐷)
5 feq3 5518 . . 3 (𝐶 = 𝐷 → (𝐺:𝐵𝐶𝐺:𝐵𝐷))
64, 5syl 14 . 2 (𝜑 → (𝐺:𝐵𝐶𝐺:𝐵𝐷))
73, 6bitrd 188 1 (𝜑 → (𝐹:𝐴𝐶𝐺:𝐵𝐷))
Colors of variables:    wff set class
This proof depends on syntax axioms:  wi 4  wb 105   = wceq 1402  wf 5373
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220
This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-v 2823  df-un 3224  df-in 3226  df-ss 3233  df-sn 3715  df-pr 3716  df-op 3718  df-br 4131  df-opab 4193  df-rel 4781  df-cnv 4782  df-co 4783  df-dm 4784  df-rn 4785  df-fun 5379  df-fn 5380  df-f 5381
This theorem is used by:  feq123  5525  feq23d  5529  csbwrdg  11336  isuhgrm  16324  uhgreq12g  16329  isuhgropm  16334  uhgrun  16339  isupgren  16348  upgrop  16357  isumgren  16358  upgrun  16379  umgrun  16381  depindlem1  16759  depindlem2  16760
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