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Theorem ovn0ssdmfun 48786
Description: If a class' operation value for two operands is not the empty set, the operands are contained in the domain of the class, and the class restricted to the operands is a function, analogous to fvfundmfvn0 6909. (Contributed by AV, 27-Jan-2020.)
Assertion
Ref Expression
ovn0ssdmfun (∀𝑎𝐷𝑏𝐸 (𝑎𝐹𝑏) ≠ ∅ → ((𝐷 × 𝐸) ⊆ dom 𝐹 ∧ Fun (𝐹 ↾ (𝐷 × 𝐸))))
Distinct variable groups:   𝐷,𝑎,𝑏   𝐸,𝑎,𝑏   𝐹,𝑎,𝑏

Proof of Theorem ovn0ssdmfun
Dummy variable 𝑝 is distinct from all other variables.
StepHypRef Expression
1 fveq2 6869 . . . . 5 (𝑝 = ⟨𝑎, 𝑏⟩ → (𝐹𝑝) = (𝐹‘⟨𝑎, 𝑏⟩))
2 df-ov 7401 . . . . 5 (𝑎𝐹𝑏) = (𝐹‘⟨𝑎, 𝑏⟩)
31, 2eqtr4di 2817 . . . 4 (𝑝 = ⟨𝑎, 𝑏⟩ → (𝐹𝑝) = (𝑎𝐹𝑏))
43neeq1d 3018 . . 3 (𝑝 = ⟨𝑎, 𝑏⟩ → ((𝐹𝑝) ≠ ∅ ↔ (𝑎𝐹𝑏) ≠ ∅))
54ralxp 5815 . 2 (∀𝑝 ∈ (𝐷 × 𝐸)(𝐹𝑝) ≠ ∅ ↔ ∀𝑎𝐷𝑏𝐸 (𝑎𝐹𝑏) ≠ ∅)
6 fvn0ssdmfun 7057 . 2 (∀𝑝 ∈ (𝐷 × 𝐸)(𝐹𝑝) ≠ ∅ → ((𝐷 × 𝐸) ⊆ dom 𝐹 ∧ Fun (𝐹 ↾ (𝐷 × 𝐸))))
75, 6sylbir 237 1 (∀𝑎𝐷𝑏𝐸 (𝑎𝐹𝑏) ≠ ∅ → ((𝐷 × 𝐸) ⊆ dom 𝐹 ∧ Fun (𝐹 ↾ (𝐷 × 𝐸))))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 399   = wceq 1562  wne 2959  wral 3078  wss 3906  c0 4287  cop 4590   × cxp 5647  dom cdm 5649  cres 5651  Fun wfun 6517  cfv 6523  (class class class)co 7398
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1817  ax-4 1831  ax-5 1932  ax-6 1989  ax-7 2030  ax-8 2146  ax-9 2154  ax-10 2177  ax-11 2193  ax-12 2214  ax-ext 2736  ax-sep 5248  ax-nul 5258  ax-pr 5392
This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3an 1101  df-tru 1565  df-fal 1575  df-ex 1802  df-nf 1806  df-sb 2093  df-mo 2568  df-eu 2598  df-clab 2743  df-cleq 2756  df-clel 2839  df-nfc 2913  df-ne 2960  df-ral 3079  df-rex 3089  df-rab 3417  df-v 3458  df-sbc 3747  df-csb 3855  df-dif 3909  df-un 3911  df-in 3913  df-ss 3923  df-nul 4288  df-if 4483  df-sn 4585  df-pr 4587  df-op 4591  df-uni 4868  df-iun 4953  df-br 5103  df-opab 5165  df-id 5544  df-xp 5655  df-rel 5656  df-cnv 5657  df-co 5658  df-dm 5659  df-res 5661  df-iota 6479  df-fun 6525  df-fv 6531  df-ov 7401
This theorem is referenced by: (None)
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