Theorem r19.42v 2546

Description: Restricted version of Theorem 19.42 of [Margaris] p. 90. (Contributed by NM, 27-May-1998.)

Assertion

Ref	Expression
r19.42v	⊢ (∃𝑥 ∈ 𝐴 (𝜑 ∧ 𝜓) ↔ (𝜑 ∧ ∃𝑥 ∈ 𝐴 𝜓))

Distinct variable group:   𝜑,𝑥

Allowed substitution hints:   𝜓(𝑥)   𝐴(𝑥)

Proof of Theorem r19.42v

Step	Hyp	Ref	Expression
1		r19.41v 2545	. 2 ⊢ (∃𝑥 ∈ 𝐴 (𝜓 ∧ 𝜑) ↔ (∃𝑥 ∈ 𝐴 𝜓 ∧ 𝜑))
2		ancom 264	. . 3 ⊢ ((𝜑 ∧ 𝜓) ↔ (𝜓 ∧ 𝜑))
3	2	rexbii 2401	. 2 ⊢ (∃𝑥 ∈ 𝐴 (𝜑 ∧ 𝜓) ↔ ∃𝑥 ∈ 𝐴 (𝜓 ∧ 𝜑))
4		ancom 264	. 2 ⊢ ((𝜑 ∧ ∃𝑥 ∈ 𝐴 𝜓) ↔ (∃𝑥 ∈ 𝐴 𝜓 ∧ 𝜑))
5	1, 3, 4	3bitr4i 211	1 ⊢ (∃𝑥 ∈ 𝐴 (𝜑 ∧ 𝜓) ↔ (𝜑 ∧ ∃𝑥 ∈ 𝐴 𝜓))

Syntax hints:   ∧ wa 103   ↔ wb 104  ∃wrex 2376

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1391  ax-gen 1393  ax-ie1 1437  ax-ie2 1438  ax-4 1455  ax-17 1474  ax-ial 1482

This theorem depends on definitions:  df-bi 116  df-tru 1302  df-nf 1405  df-rex 2381

This theorem is referenced by:  ceqsrexbv  2770  ceqsrex2v  2771  2reuswapdc  2841  iunrab  3807  iunin2  3823  iundif2ss  3825  iunopab  4141  elxp2  4495  cnvuni  4663  elunirn  5599  f1oiso  5659  oprabrexex2  5959  genpdflem  7216  1idprl  7299  1idpru  7300  ltexprlemm  7309  rexuz2  9226  4fvwrd4  9758  divalgb  11417