Theorem cbvabw 2833

Description: Rule used to change bound variables, using implicit substitution. Version of cbvab 2834 with a disjoint variable condition, which does not require ax-10 2175, ax-13 2403. (Contributed by Andrew Salmon, 11-Jul-2011.) (Revised by GG, 23-May-2024.)

Hypotheses

Ref	Expression
cbvabw.1	⊢ Ⅎ𝑦𝜑
cbvabw.2	⊢ Ⅎ𝑥𝜓
cbvabw.3	⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓))

Assertion

Ref	Expression
cbvabw	⊢ {𝑥 ∣ 𝜑} = {𝑦 ∣ 𝜓}

Distinct variable group:   𝑥,𝑦

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

Proof of Theorem cbvabw

Dummy variable 𝑧 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		cbvabw.1	. . . 4 ⊢ Ⅎ𝑦𝜑
2		cbvabw.2	. . . 4 ⊢ Ⅎ𝑥𝜓
3		cbvabw.3	. . . 4 ⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓))
4	1, 2, 3	cbvsbvf 2394	. . 3 ⊢ ([𝑧 / 𝑥]𝜑 ↔ [𝑧 / 𝑦]𝜓)
5		df-clab 2741	. . 3 ⊢ (𝑧 ∈ {𝑥 ∣ 𝜑} ↔ [𝑧 / 𝑥]𝜑)
6		df-clab 2741	. . 3 ⊢ (𝑧 ∈ {𝑦 ∣ 𝜓} ↔ [𝑧 / 𝑦]𝜓)
7	4, 5, 6	3bitr4i 306	. 2 ⊢ (𝑧 ∈ {𝑥 ∣ 𝜑} ↔ 𝑧 ∈ {𝑦 ∣ 𝜓})
8	7	eqriv 2759	1 ⊢ {𝑥 ∣ 𝜑} = {𝑦 ∣ 𝜓}

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   = wceq 1569  Ⅎwnf 1812  [wsb 2095   ∈ wcel 2142  {cab 2740

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1824  ax-4 1838  ax-5 1939  ax-6 1996  ax-7 2037  ax-9 2152  ax-11 2191  ax-12 2212  ax-ext 2734

This proof depends on definitions:  df-bi 210  df-an 401  df-ex 1809  df-nf 1813  df-sb 2096  df-clab 2741  df-cleq 2754

This theorem is used by:  cbvrabw  3450  cbvsbcw  3776  cbvrabcsfw  3893  rabsnifsb  4687  dfdmf  5885  dfrnf  5939  funfv2f  6970  abrexex2g  7959  bnj873  35321  fineqvrep  35535  ptrest  38298  poimirlem26  38325  poimirlem27  38326