Theorem reueqdv 3400

Description: Formula-building rule for restricted existential uniqueness quantifier. Deduction form. (Contributed by GG, 1-Sep-2025.)

Hypothesis

Ref	Expression
reueqdv.1	⊢ (𝜑 → 𝐴 = 𝐵)

Assertion

Ref	Expression
reueqdv	⊢ (𝜑 → (∃!𝑥 ∈ 𝐴 𝜓 ↔ ∃!𝑥 ∈ 𝐵 𝜓))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

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

Proof of Theorem reueqdv

Step	Hyp	Ref	Expression
1		reueqdv.1	. 2 ⊢ (𝜑 → 𝐴 = 𝐵)
2		reueq1 3397	. 2 ⊢ (𝐴 = 𝐵 → (∃!𝑥 ∈ 𝐴 𝜓 ↔ ∃!𝑥 ∈ 𝐵 𝜓))
3	1, 2	syl 18	1 ⊢ (𝜑 → (∃!𝑥 ∈ 𝐴 𝜓 ↔ ∃!𝑥 ∈ 𝐵 𝜓))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   = wceq 1570  ∃!wreu 3363

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-9 2155  ax-ext 2732

This proof depends on definitions:  df-bi 210  df-an 402  df-ex 1813  df-mo 2564  df-eu 2594  df-cleq 2752  df-rex 3087  df-rmo 3365  df-reu 3366

This theorem is used by:  reueqbidva  49838