Users' Mathboxes Mathbox for Alexander van der Vekens < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  ovn0ssdmfun Structured version   Visualization version   GIF version

Theorem ovn0ssdmfun 45209
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 6794. (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 6756 . . . . 5 (𝑝 = ⟨𝑎, 𝑏⟩ → (𝐹𝑝) = (𝐹‘⟨𝑎, 𝑏⟩))
2 df-ov 7258 . . . . 5 (𝑎𝐹𝑏) = (𝐹‘⟨𝑎, 𝑏⟩)
31, 2eqtr4di 2797 . . . 4 (𝑝 = ⟨𝑎, 𝑏⟩ → (𝐹𝑝) = (𝑎𝐹𝑏))
43neeq1d 3002 . . 3 (𝑝 = ⟨𝑎, 𝑏⟩ → ((𝐹𝑝) ≠ ∅ ↔ (𝑎𝐹𝑏) ≠ ∅))
54ralxp 5739 . 2 (∀𝑝 ∈ (𝐷 × 𝐸)(𝐹𝑝) ≠ ∅ ↔ ∀𝑎𝐷𝑏𝐸 (𝑎𝐹𝑏) ≠ ∅)
6 fvn0ssdmfun 6934 . 2 (∀𝑝 ∈ (𝐷 × 𝐸)(𝐹𝑝) ≠ ∅ → ((𝐷 × 𝐸) ⊆ dom 𝐹 ∧ Fun (𝐹 ↾ (𝐷 × 𝐸))))
75, 6sylbir 234 1 (∀𝑎𝐷𝑏𝐸 (𝑎𝐹𝑏) ≠ ∅ → ((𝐷 × 𝐸) ⊆ dom 𝐹 ∧ Fun (𝐹 ↾ (𝐷 × 𝐸))))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 395   = wceq 1539  wne 2942  wral 3063  wss 3883  c0 4253  cop 4564   × cxp 5578  dom cdm 5580  cres 5582  Fun wfun 6412  cfv 6418  (class class class)co 7255
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1799  ax-4 1813  ax-5 1914  ax-6 1972  ax-7 2012  ax-8 2110  ax-9 2118  ax-10 2139  ax-11 2156  ax-12 2173  ax-ext 2709  ax-sep 5218  ax-nul 5225  ax-pr 5347
This theorem depends on definitions:  df-bi 206  df-an 396  df-or 844  df-3an 1087  df-tru 1542  df-fal 1552  df-ex 1784  df-nf 1788  df-sb 2069  df-mo 2540  df-eu 2569  df-clab 2716  df-cleq 2730  df-clel 2817  df-nfc 2888  df-ne 2943  df-ral 3068  df-rex 3069  df-rab 3072  df-v 3424  df-sbc 3712  df-csb 3829  df-dif 3886  df-un 3888  df-in 3890  df-ss 3900  df-nul 4254  df-if 4457  df-sn 4559  df-pr 4561  df-op 4565  df-uni 4837  df-iun 4923  df-br 5071  df-opab 5133  df-id 5480  df-xp 5586  df-rel 5587  df-cnv 5588  df-co 5589  df-dm 5590  df-res 5592  df-iota 6376  df-fun 6420  df-fv 6426  df-ov 7258
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator