Theorem reubidva 3367

Description: Formula-building rule for restricted existential quantifier (deduction form). (Contributed by NM, 13-Nov-2004.) Reduce axiom usage. (Revised by Wolf Lammen, 14-Jan-2023.)

Hypothesis

Ref	Expression
rmobidva.1	⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → (𝜓 ↔ 𝜒))

Assertion

Ref	Expression
reubidva	⊢ (𝜑 → (∃!𝑥 ∈ 𝐴 𝜓 ↔ ∃!𝑥 ∈ 𝐴 𝜒))

Distinct variable group:   𝜑,𝑥

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

Proof of Theorem reubidva

Step	Hyp	Ref	Expression
1		rmobidva.1	. . . 4 ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → (𝜓 ↔ 𝜒))
2	1	pm5.32da 579	. . 3 ⊢ (𝜑 → ((𝑥 ∈ 𝐴 ∧ 𝜓) ↔ (𝑥 ∈ 𝐴 ∧ 𝜒)))
3	2	eubidv 2579	. 2 ⊢ (𝜑 → (∃!𝑥(𝑥 ∈ 𝐴 ∧ 𝜓) ↔ ∃!𝑥(𝑥 ∈ 𝐴 ∧ 𝜒)))
4		df-reu 3352	. 2 ⊢ (∃!𝑥 ∈ 𝐴 𝜓 ↔ ∃!𝑥(𝑥 ∈ 𝐴 ∧ 𝜓))
5		df-reu 3352	. 2 ⊢ (∃!𝑥 ∈ 𝐴 𝜒 ↔ ∃!𝑥(𝑥 ∈ 𝐴 ∧ 𝜒))
6	3, 4, 5	3bitr4g 313	1 ⊢ (𝜑 → (∃!𝑥 ∈ 𝐴 𝜓 ↔ ∃!𝑥 ∈ 𝐴 𝜒))

Syntax hints:   → wi 4   ↔ wb 205   ∧ wa 396   ∈ wcel 2106  ∃!weu 2561  ∃!wreu 3349

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913

This theorem depends on definitions:  df-bi 206  df-an 397  df-ex 1782  df-mo 2533  df-eu 2562  df-reu 3352

This theorem is referenced by:  reubidv  3369  reuxfrd  3709  reuxfr1d  3711  exfo  7060  f1ofveu  7356  zmax  12879  zbtwnre  12880  rebtwnz  12881  icoshftf1o  13401  divalgb  16297  1arith2  16811  ply1divalg2  25540  addsq2reu  26825  addsqn2reu  26826  addsqrexnreu  26827  2sqreultlem  26832  2sqreunnltlem  26835  frgr2wwlkeu  29334  numclwwlk2lem1  29383  numclwlk2lem2f1o  29386  pjhtheu2  30421  reuxfrdf  31483  xrsclat  31941  xrmulc1cn  32600  poimirlem25  36176  hdmap14lem14  40417  cantnf2  41718  prproropreud  45821  quad1  45932  requad1  45934  requad2  45935  itscnhlinecirc02p  46991