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Theorem cbvreucsf 3162
Description: A more general version of cbvreuv 2741 that has no distinct variable rextrictions. Changes bound variables using implicit substitution. (Contributed by Andrew Salmon, 13-Jul-2011.)
Hypotheses
Ref Expression
cbvralcsf.1 𝑦𝐴
cbvralcsf.2 𝑥𝐵
cbvralcsf.3 𝑦𝜑
cbvralcsf.4 𝑥𝜓
cbvralcsf.5 (𝑥 = 𝑦𝐴 = 𝐵)
cbvralcsf.6 (𝑥 = 𝑦 → (𝜑𝜓))
Assertion
Ref Expression
cbvreucsf (∃!𝑥𝐴 𝜑 ↔ ∃!𝑦𝐵 𝜓)

Proof of Theorem cbvreucsf
Dummy variables 𝑣 𝑧 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 nfv 1552 . . . 4 𝑧(𝑥𝐴𝜑)
2 nfcsb1v 3130 . . . . . 6 𝑥𝑧 / 𝑥𝐴
32nfcri 2343 . . . . 5 𝑥 𝑧𝑧 / 𝑥𝐴
4 nfs1v 1968 . . . . 5 𝑥[𝑧 / 𝑥]𝜑
53, 4nfan 1589 . . . 4 𝑥(𝑧𝑧 / 𝑥𝐴 ∧ [𝑧 / 𝑥]𝜑)
6 id 19 . . . . . 6 (𝑥 = 𝑧𝑥 = 𝑧)
7 csbeq1a 3106 . . . . . 6 (𝑥 = 𝑧𝐴 = 𝑧 / 𝑥𝐴)
86, 7eleq12d 2277 . . . . 5 (𝑥 = 𝑧 → (𝑥𝐴𝑧𝑧 / 𝑥𝐴))
9 sbequ12 1795 . . . . 5 (𝑥 = 𝑧 → (𝜑 ↔ [𝑧 / 𝑥]𝜑))
108, 9anbi12d 473 . . . 4 (𝑥 = 𝑧 → ((𝑥𝐴𝜑) ↔ (𝑧𝑧 / 𝑥𝐴 ∧ [𝑧 / 𝑥]𝜑)))
111, 5, 10cbveu 2079 . . 3 (∃!𝑥(𝑥𝐴𝜑) ↔ ∃!𝑧(𝑧𝑧 / 𝑥𝐴 ∧ [𝑧 / 𝑥]𝜑))
12 nfcv 2349 . . . . . . 7 𝑦𝑧
13 cbvralcsf.1 . . . . . . 7 𝑦𝐴
1412, 13nfcsb 3135 . . . . . 6 𝑦𝑧 / 𝑥𝐴
1514nfcri 2343 . . . . 5 𝑦 𝑧𝑧 / 𝑥𝐴
16 cbvralcsf.3 . . . . . 6 𝑦𝜑
1716nfsb 1975 . . . . 5 𝑦[𝑧 / 𝑥]𝜑
1815, 17nfan 1589 . . . 4 𝑦(𝑧𝑧 / 𝑥𝐴 ∧ [𝑧 / 𝑥]𝜑)
19 nfv 1552 . . . 4 𝑧(𝑦𝐵𝜓)
20 id 19 . . . . . 6 (𝑧 = 𝑦𝑧 = 𝑦)
21 csbeq1 3100 . . . . . . 7 (𝑧 = 𝑦𝑧 / 𝑥𝐴 = 𝑦 / 𝑥𝐴)
22 sbsbc 3006 . . . . . . . . 9 ([𝑦 / 𝑥]𝑣𝐴[𝑦 / 𝑥]𝑣𝐴)
2322abbii 2322 . . . . . . . 8 {𝑣 ∣ [𝑦 / 𝑥]𝑣𝐴} = {𝑣[𝑦 / 𝑥]𝑣𝐴}
24 cbvralcsf.2 . . . . . . . . . . . 12 𝑥𝐵
2524nfcri 2343 . . . . . . . . . . 11 𝑥 𝑣𝐵
26 cbvralcsf.5 . . . . . . . . . . . 12 (𝑥 = 𝑦𝐴 = 𝐵)
2726eleq2d 2276 . . . . . . . . . . 11 (𝑥 = 𝑦 → (𝑣𝐴𝑣𝐵))
2825, 27sbie 1815 . . . . . . . . . 10 ([𝑦 / 𝑥]𝑣𝐴𝑣𝐵)
2928bicomi 132 . . . . . . . . 9 (𝑣𝐵 ↔ [𝑦 / 𝑥]𝑣𝐴)
3029abbi2i 2321 . . . . . . . 8 𝐵 = {𝑣 ∣ [𝑦 / 𝑥]𝑣𝐴}
31 df-csb 3098 . . . . . . . 8 𝑦 / 𝑥𝐴 = {𝑣[𝑦 / 𝑥]𝑣𝐴}
3223, 30, 313eqtr4ri 2238 . . . . . . 7 𝑦 / 𝑥𝐴 = 𝐵
3321, 32eqtrdi 2255 . . . . . 6 (𝑧 = 𝑦𝑧 / 𝑥𝐴 = 𝐵)
3420, 33eleq12d 2277 . . . . 5 (𝑧 = 𝑦 → (𝑧𝑧 / 𝑥𝐴𝑦𝐵))
35 sbequ 1864 . . . . . 6 (𝑧 = 𝑦 → ([𝑧 / 𝑥]𝜑 ↔ [𝑦 / 𝑥]𝜑))
36 cbvralcsf.4 . . . . . . 7 𝑥𝜓
37 cbvralcsf.6 . . . . . . 7 (𝑥 = 𝑦 → (𝜑𝜓))
3836, 37sbie 1815 . . . . . 6 ([𝑦 / 𝑥]𝜑𝜓)
3935, 38bitrdi 196 . . . . 5 (𝑧 = 𝑦 → ([𝑧 / 𝑥]𝜑𝜓))
4034, 39anbi12d 473 . . . 4 (𝑧 = 𝑦 → ((𝑧𝑧 / 𝑥𝐴 ∧ [𝑧 / 𝑥]𝜑) ↔ (𝑦𝐵𝜓)))
4118, 19, 40cbveu 2079 . . 3 (∃!𝑧(𝑧𝑧 / 𝑥𝐴 ∧ [𝑧 / 𝑥]𝜑) ↔ ∃!𝑦(𝑦𝐵𝜓))
4211, 41bitri 184 . 2 (∃!𝑥(𝑥𝐴𝜑) ↔ ∃!𝑦(𝑦𝐵𝜓))
43 df-reu 2492 . 2 (∃!𝑥𝐴 𝜑 ↔ ∃!𝑥(𝑥𝐴𝜑))
44 df-reu 2492 . 2 (∃!𝑦𝐵 𝜓 ↔ ∃!𝑦(𝑦𝐵𝜓))
4542, 43, 443bitr4i 212 1 (∃!𝑥𝐴 𝜑 ↔ ∃!𝑦𝐵 𝜓)
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104  wb 105   = wceq 1373  wnf 1484  [wsb 1786  ∃!weu 2055  wcel 2177  {cab 2192  wnfc 2336  ∃!wreu 2487  [wsbc 3002  csb 3097
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-ext 2188
This theorem depends on definitions:  df-bi 117  df-tru 1376  df-nf 1485  df-sb 1787  df-eu 2058  df-clab 2193  df-cleq 2199  df-clel 2202  df-nfc 2338  df-reu 2492  df-sbc 3003  df-csb 3098
This theorem is referenced by: (None)
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