Users' Mathboxes Mathbox for BJ < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  bj-prexg Structured version   Visualization version   GIF version

Theorem bj-prexg 37515
Description: Existence of unordered pairs formed on sets, proved from ax-bj-sn 37509 and ax-bj-bun 37513. Contrary to bj-prex 37516, this proof is intuitionistically valid and does not require ax-nul 5257. (Contributed by BJ, 12-Jan-2025.) (Proof modification is discouraged.)
Assertion
Ref Expression
bj-prexg ((𝐴𝑉𝐵𝑊) → {𝐴, 𝐵} ∈ V)

Proof of Theorem bj-prexg
StepHypRef Expression
1 df-pr 4586 . 2 {𝐴, 𝐵} = ({𝐴} ∪ {𝐵})
2 bj-snexg 37510 . . 3 (𝐴𝑉 → {𝐴} ∈ V)
3 bj-snexg 37510 . . 3 (𝐵𝑊 → {𝐵} ∈ V)
4 bj-unexg 37514 . . 3 (({𝐴} ∈ V ∧ {𝐵} ∈ V) → ({𝐴} ∪ {𝐵}) ∈ V)
52, 3, 4syl2an 605 . 2 ((𝐴𝑉𝐵𝑊) → ({𝐴} ∪ {𝐵}) ∈ V)
61, 5eqeltrid 2867 1 ((𝐴𝑉𝐵𝑊) → {𝐴, 𝐵} ∈ V)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 399  wcel 2143  Vcvv 3455  cun 3903  {csn 4583  {cpr 4585
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1816  ax-4 1830  ax-5 1931  ax-6 1988  ax-7 2029  ax-8 2145  ax-9 2153  ax-12 2213  ax-ext 2735  ax-bj-sn 37509  ax-bj-bun 37513
This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-tru 1564  df-ex 1801  df-sb 2092  df-clab 2742  df-cleq 2755  df-clel 2838  df-v 3457  df-un 3910  df-sn 4584  df-pr 4586
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator