Theorem cbvral2vw 3220

Description: Change bound variables of double restricted universal quantification, using implicit substitution. Version of cbvral2v 3340 with a disjoint variable condition, which does not require ax-13 2377. (Contributed by NM, 10-Aug-2004.) Avoid ax-13 2377. (Revised by GG, 10-Jan-2024.)

Hypotheses

Ref	Expression
cbvral2vw.1	⊢ (𝑥 = 𝑧 → (𝜑 ↔ 𝜒))
cbvral2vw.2	⊢ (𝑦 = 𝑤 → (𝜒 ↔ 𝜓))

Assertion

Ref	Expression
cbvral2vw	⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑧 ∈ 𝐴 ∀𝑤 ∈ 𝐵 𝜓)

Distinct variable groups:   𝑥,𝑧   𝑦,𝑤   𝑥,𝐴,𝑧   𝑥,𝑦,𝐵,𝑧   𝑤,𝐵   𝜑,𝑧   𝜓,𝑦   𝜒,𝑥   𝜒,𝑤

Allowed substitution hints:   𝜑(𝑥,𝑦,𝑤)   𝜓(𝑥,𝑧,𝑤)   𝜒(𝑦,𝑧)   𝐴(𝑦,𝑤)

Proof of Theorem cbvral2vw

Step	Hyp	Ref	Expression
1		cbvral2vw.1	. . . 4 ⊢ (𝑥 = 𝑧 → (𝜑 ↔ 𝜒))
2	1	ralbidv 3161	. . 3 ⊢ (𝑥 = 𝑧 → (∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑦 ∈ 𝐵 𝜒))
3	2	cbvralvw 3216	. 2 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑧 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜒)
4		cbvral2vw.2	. . . 4 ⊢ (𝑦 = 𝑤 → (𝜒 ↔ 𝜓))
5	4	cbvralvw 3216	. . 3 ⊢ (∀𝑦 ∈ 𝐵 𝜒 ↔ ∀𝑤 ∈ 𝐵 𝜓)
6	5	ralbii 3084	. 2 ⊢ (∀𝑧 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜒 ↔ ∀𝑧 ∈ 𝐴 ∀𝑤 ∈ 𝐵 𝜓)
7	3, 6	bitri 275	1 ⊢ (∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 𝜑 ↔ ∀𝑧 ∈ 𝐴 ∀𝑤 ∈ 𝐵 𝜓)

Syntax hints:   → wi 4   ↔ wb 206  ∀wral 3052

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 1912  ax-6 1969  ax-7 2010  ax-8 2116

This theorem depends on definitions:  df-bi 207  df-an 396  df-ex 1782  df-clel 2812  df-ral 3053

This theorem is referenced by:  cbvral3vw  3222  cbvral6vw  3224  fununi  6575  fiint  9239  nqereu  10852  mgmhmpropd  18635  mhmpropd  18729  efgred  19692  mplcoe5  22010  mdetunilem9  22579  fbun  23799  fbunfip  23828  caucfil  25254  pmltpc  25422  negsprop  28046  iscgrglt  28602  axcontlem10  29062  htth  31010  cdj3lem3b  32532  cdj3i  32533  dfmgc2  33093  isros  34350  rossros  34362  fipjust  43925  isotone1  44408  isotone2  44409  ntrclsiso  44427  ntrclskb  44429  ntrclsk3  44430  ntrclsk13  44431  limsuppnfd  46064  pimincfltioo  47080  incsmf  47104  decsmf  47129  catprslem  49373  isthincd2lem1  49788  isthincd2lem2  49798