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Theorem bj-prexg 36224
Description: Existence of unordered pairs formed on sets, proved from ax-bj-sn 36218 and ax-bj-bun 36222. Contrary to bj-prex 36225, this proof is intuitionistically valid and does not require ax-nul 5306. (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 4631 . 2 {𝐴, 𝐵} = ({𝐴} ∪ {𝐵})
2 bj-snexg 36219 . . 3 (𝐴𝑉 → {𝐴} ∈ V)
3 bj-snexg 36219 . . 3 (𝐵𝑊 → {𝐵} ∈ V)
4 bj-unexg 36223 . . 3 (({𝐴} ∈ V ∧ {𝐵} ∈ V) → ({𝐴} ∪ {𝐵}) ∈ V)
52, 3, 4syl2an 595 . 2 ((𝐴𝑉𝐵𝑊) → ({𝐴} ∪ {𝐵}) ∈ V)
61, 5eqeltrid 2836 1 ((𝐴𝑉𝐵𝑊) → {𝐴, 𝐵} ∈ V)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 395  wcel 2105  Vcvv 3473  cun 3946  {csn 4628  {cpr 4630
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1912  ax-6 1970  ax-7 2010  ax-8 2107  ax-9 2115  ax-12 2170  ax-ext 2702  ax-bj-sn 36218  ax-bj-bun 36222
This theorem depends on definitions:  df-bi 206  df-an 396  df-or 845  df-tru 1543  df-ex 1781  df-sb 2067  df-clab 2709  df-cleq 2723  df-clel 2809  df-v 3475  df-un 3953  df-sn 4629  df-pr 4631
This theorem is referenced by: (None)
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