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Theorem bj-prexg 37529
Description: Existence of unordered pairs formed on sets, proved from ax-bj-sn 37523 and ax-bj-bun 37527. Contrary to bj-prex 37530, this proof is intuitionistically valid and does not require ax-nul 5258. (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 4587 . 2 {𝐴, 𝐵} = ({𝐴} ∪ {𝐵})
2 bj-snexg 37524 . . 3 (𝐴𝑉 → {𝐴} ∈ V)
3 bj-snexg 37524 . . 3 (𝐵𝑊 → {𝐵} ∈ V)
4 bj-unexg 37528 . . 3 (({𝐴} ∈ V ∧ {𝐵} ∈ V) → ({𝐴} ∪ {𝐵}) ∈ V)
52, 3, 4syl2an 605 . 2 ((𝐴𝑉𝐵𝑊) → ({𝐴} ∪ {𝐵}) ∈ V)
61, 5eqeltrid 2868 1 ((𝐴𝑉𝐵𝑊) → {𝐴, 𝐵} ∈ V)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 399  wcel 2144  Vcvv 3456  cun 3904  {csn 4584  {cpr 4586
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-12 2214  ax-ext 2736  ax-bj-sn 37523  ax-bj-bun 37527
This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-tru 1565  df-ex 1802  df-sb 2093  df-clab 2743  df-cleq 2756  df-clel 2839  df-v 3458  df-un 3911  df-sn 4585  df-pr 4587
This theorem is referenced by: (None)
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