MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  eeeanv Structured version   Visualization version   GIF version

Theorem eeeanv 2171
Description: Rearrange existential quantifiers. (Contributed by NM, 26-Jul-1995.) (Proof shortened by Andrew Salmon, 25-May-2011.) Reduce distinct variable restrictions. (Revised by Wolf Lammen, 20-Jan-2018.)
Assertion
Ref Expression
eeeanv (∃𝑥𝑦𝑧(𝜑𝜓𝜒) ↔ (∃𝑥𝜑 ∧ ∃𝑦𝜓 ∧ ∃𝑧𝜒))
Distinct variable groups:   𝜑,𝑦   𝜑,𝑧   𝜓,𝑥   𝜓,𝑧   𝜒,𝑥   𝜒,𝑦
Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑦)   𝜒(𝑧)

Proof of Theorem eeeanv
StepHypRef Expression
1 eeanv 2170 . . 3 (∃𝑥𝑦(𝜑𝜓) ↔ (∃𝑥𝜑 ∧ ∃𝑦𝜓))
21anbi1i 727 . 2 ((∃𝑥𝑦(𝜑𝜓) ∧ ∃𝑧𝜒) ↔ ((∃𝑥𝜑 ∧ ∃𝑦𝜓) ∧ ∃𝑧𝜒))
3 df-3an 1033 . . . . . 6 ((𝜑𝜓𝜒) ↔ ((𝜑𝜓) ∧ 𝜒))
43exbii 1764 . . . . 5 (∃𝑧(𝜑𝜓𝜒) ↔ ∃𝑧((𝜑𝜓) ∧ 𝜒))
5 19.42v 1905 . . . . 5 (∃𝑧((𝜑𝜓) ∧ 𝜒) ↔ ((𝜑𝜓) ∧ ∃𝑧𝜒))
64, 5bitri 263 . . . 4 (∃𝑧(𝜑𝜓𝜒) ↔ ((𝜑𝜓) ∧ ∃𝑧𝜒))
762exbii 1765 . . 3 (∃𝑥𝑦𝑧(𝜑𝜓𝜒) ↔ ∃𝑥𝑦((𝜑𝜓) ∧ ∃𝑧𝜒))
8 nfv 1830 . . . . . 6 𝑦𝜒
98nfex 2140 . . . . 5 𝑦𝑧𝜒
10919.41 2090 . . . 4 (∃𝑦((𝜑𝜓) ∧ ∃𝑧𝜒) ↔ (∃𝑦(𝜑𝜓) ∧ ∃𝑧𝜒))
1110exbii 1764 . . 3 (∃𝑥𝑦((𝜑𝜓) ∧ ∃𝑧𝜒) ↔ ∃𝑥(∃𝑦(𝜑𝜓) ∧ ∃𝑧𝜒))
12 nfv 1830 . . . . 5 𝑥𝜒
1312nfex 2140 . . . 4 𝑥𝑧𝜒
141319.41 2090 . . 3 (∃𝑥(∃𝑦(𝜑𝜓) ∧ ∃𝑧𝜒) ↔ (∃𝑥𝑦(𝜑𝜓) ∧ ∃𝑧𝜒))
157, 11, 143bitri 285 . 2 (∃𝑥𝑦𝑧(𝜑𝜓𝜒) ↔ (∃𝑥𝑦(𝜑𝜓) ∧ ∃𝑧𝜒))
16 df-3an 1033 . 2 ((∃𝑥𝜑 ∧ ∃𝑦𝜓 ∧ ∃𝑧𝜒) ↔ ((∃𝑥𝜑 ∧ ∃𝑦𝜓) ∧ ∃𝑧𝜒))
172, 15, 163bitr4i 291 1 (∃𝑥𝑦𝑧(𝜑𝜓𝜒) ↔ (∃𝑥𝜑 ∧ ∃𝑦𝜓 ∧ ∃𝑧𝜒))
Colors of variables: wff setvar class
Syntax hints:  wb 195  wa 383  w3a 1031  wex 1695
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-10 2006  ax-11 2021  ax-12 2034
This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3an 1033  df-ex 1696  df-nf 1701
This theorem is referenced by:  vtocl3  3235  spc3egv  3270  eloprabga  6645
  Copyright terms: Public domain W3C validator