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Theorem dff13f 6553
Description: A one-to-one function in terms of function values. Compare Theorem 4.8(iv) of [Monk1] p. 43. (Contributed by NM, 31-Jul-2003.)
Hypotheses
Ref Expression
dff13f.1 𝑥𝐹
dff13f.2 𝑦𝐹
Assertion
Ref Expression
dff13f (𝐹:𝐴1-1𝐵 ↔ (𝐹:𝐴𝐵 ∧ ∀𝑥𝐴𝑦𝐴 ((𝐹𝑥) = (𝐹𝑦) → 𝑥 = 𝑦)))
Distinct variable group:   𝑥,𝑦,𝐴
Allowed substitution hints:   𝐵(𝑥,𝑦)   𝐹(𝑥,𝑦)

Proof of Theorem dff13f
Dummy variables 𝑤 𝑣 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 dff13 6552 . 2 (𝐹:𝐴1-1𝐵 ↔ (𝐹:𝐴𝐵 ∧ ∀𝑤𝐴𝑣𝐴 ((𝐹𝑤) = (𝐹𝑣) → 𝑤 = 𝑣)))
2 dff13f.2 . . . . . . . . 9 𝑦𝐹
3 nfcv 2793 . . . . . . . . 9 𝑦𝑤
42, 3nffv 6236 . . . . . . . 8 𝑦(𝐹𝑤)
5 nfcv 2793 . . . . . . . . 9 𝑦𝑣
62, 5nffv 6236 . . . . . . . 8 𝑦(𝐹𝑣)
74, 6nfeq 2805 . . . . . . 7 𝑦(𝐹𝑤) = (𝐹𝑣)
8 nfv 1883 . . . . . . 7 𝑦 𝑤 = 𝑣
97, 8nfim 1865 . . . . . 6 𝑦((𝐹𝑤) = (𝐹𝑣) → 𝑤 = 𝑣)
10 nfv 1883 . . . . . 6 𝑣((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦)
11 fveq2 6229 . . . . . . . 8 (𝑣 = 𝑦 → (𝐹𝑣) = (𝐹𝑦))
1211eqeq2d 2661 . . . . . . 7 (𝑣 = 𝑦 → ((𝐹𝑤) = (𝐹𝑣) ↔ (𝐹𝑤) = (𝐹𝑦)))
13 equequ2 1999 . . . . . . 7 (𝑣 = 𝑦 → (𝑤 = 𝑣𝑤 = 𝑦))
1412, 13imbi12d 333 . . . . . 6 (𝑣 = 𝑦 → (((𝐹𝑤) = (𝐹𝑣) → 𝑤 = 𝑣) ↔ ((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦)))
159, 10, 14cbvral 3197 . . . . 5 (∀𝑣𝐴 ((𝐹𝑤) = (𝐹𝑣) → 𝑤 = 𝑣) ↔ ∀𝑦𝐴 ((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦))
1615ralbii 3009 . . . 4 (∀𝑤𝐴𝑣𝐴 ((𝐹𝑤) = (𝐹𝑣) → 𝑤 = 𝑣) ↔ ∀𝑤𝐴𝑦𝐴 ((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦))
17 nfcv 2793 . . . . . 6 𝑥𝐴
18 dff13f.1 . . . . . . . . 9 𝑥𝐹
19 nfcv 2793 . . . . . . . . 9 𝑥𝑤
2018, 19nffv 6236 . . . . . . . 8 𝑥(𝐹𝑤)
21 nfcv 2793 . . . . . . . . 9 𝑥𝑦
2218, 21nffv 6236 . . . . . . . 8 𝑥(𝐹𝑦)
2320, 22nfeq 2805 . . . . . . 7 𝑥(𝐹𝑤) = (𝐹𝑦)
24 nfv 1883 . . . . . . 7 𝑥 𝑤 = 𝑦
2523, 24nfim 1865 . . . . . 6 𝑥((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦)
2617, 25nfral 2974 . . . . 5 𝑥𝑦𝐴 ((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦)
27 nfv 1883 . . . . 5 𝑤𝑦𝐴 ((𝐹𝑥) = (𝐹𝑦) → 𝑥 = 𝑦)
28 fveq2 6229 . . . . . . . 8 (𝑤 = 𝑥 → (𝐹𝑤) = (𝐹𝑥))
2928eqeq1d 2653 . . . . . . 7 (𝑤 = 𝑥 → ((𝐹𝑤) = (𝐹𝑦) ↔ (𝐹𝑥) = (𝐹𝑦)))
30 equequ1 1998 . . . . . . 7 (𝑤 = 𝑥 → (𝑤 = 𝑦𝑥 = 𝑦))
3129, 30imbi12d 333 . . . . . 6 (𝑤 = 𝑥 → (((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦) ↔ ((𝐹𝑥) = (𝐹𝑦) → 𝑥 = 𝑦)))
3231ralbidv 3015 . . . . 5 (𝑤 = 𝑥 → (∀𝑦𝐴 ((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦) ↔ ∀𝑦𝐴 ((𝐹𝑥) = (𝐹𝑦) → 𝑥 = 𝑦)))
3326, 27, 32cbvral 3197 . . . 4 (∀𝑤𝐴𝑦𝐴 ((𝐹𝑤) = (𝐹𝑦) → 𝑤 = 𝑦) ↔ ∀𝑥𝐴𝑦𝐴 ((𝐹𝑥) = (𝐹𝑦) → 𝑥 = 𝑦))
3416, 33bitri 264 . . 3 (∀𝑤𝐴𝑣𝐴 ((𝐹𝑤) = (𝐹𝑣) → 𝑤 = 𝑣) ↔ ∀𝑥𝐴𝑦𝐴 ((𝐹𝑥) = (𝐹𝑦) → 𝑥 = 𝑦))
3534anbi2i 730 . 2 ((𝐹:𝐴𝐵 ∧ ∀𝑤𝐴𝑣𝐴 ((𝐹𝑤) = (𝐹𝑣) → 𝑤 = 𝑣)) ↔ (𝐹:𝐴𝐵 ∧ ∀𝑥𝐴𝑦𝐴 ((𝐹𝑥) = (𝐹𝑦) → 𝑥 = 𝑦)))
361, 35bitri 264 1 (𝐹:𝐴1-1𝐵 ↔ (𝐹:𝐴𝐵 ∧ ∀𝑥𝐴𝑦𝐴 ((𝐹𝑥) = (𝐹𝑦) → 𝑥 = 𝑦)))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 196  wa 383   = wceq 1523  wnfc 2780  wral 2941  wf 5922  1-1wf1 5923  cfv 5926
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1762  ax-4 1777  ax-5 1879  ax-6 1945  ax-7 1981  ax-9 2039  ax-10 2059  ax-11 2074  ax-12 2087  ax-13 2282  ax-ext 2631  ax-sep 4814  ax-nul 4822  ax-pr 4936
This theorem depends on definitions:  df-bi 197  df-or 384  df-an 385  df-3an 1056  df-tru 1526  df-ex 1745  df-nf 1750  df-sb 1938  df-eu 2502  df-mo 2503  df-clab 2638  df-cleq 2644  df-clel 2647  df-nfc 2782  df-ral 2946  df-rex 2947  df-rab 2950  df-v 3233  df-sbc 3469  df-dif 3610  df-un 3612  df-in 3614  df-ss 3621  df-nul 3949  df-if 4120  df-sn 4211  df-pr 4213  df-op 4217  df-uni 4469  df-br 4686  df-opab 4746  df-id 5053  df-xp 5149  df-rel 5150  df-cnv 5151  df-co 5152  df-dm 5153  df-iota 5889  df-fun 5928  df-fn 5929  df-f 5930  df-f1 5931  df-fv 5934
This theorem is referenced by:  f1mpt  6558  dom2lem  8037
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