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Theorem nfsbcdw 3131
Description: Version of nfsbcd 3022 with a disjoint variable condition. (Contributed by NM, 23-Nov-2005.) (Revised by GG, 10-Jan-2024.)
Hypotheses
Ref Expression
nfsbcdw.1 𝑦𝜑
nfsbcdw.2 (𝜑𝑥𝐴)
nfsbcdw.3 (𝜑 → Ⅎ𝑥𝜓)
Assertion
Ref Expression
nfsbcdw (𝜑 → Ⅎ𝑥[𝐴 / 𝑦]𝜓)
Distinct variable group:   𝑥,𝑦
Allowed substitution hints:   𝜑(𝑥,𝑦)   𝜓(𝑥,𝑦)   𝐴(𝑥,𝑦)

Proof of Theorem nfsbcdw
StepHypRef Expression
1 df-sbc 3003 . 2 ([𝐴 / 𝑦]𝜓𝐴 ∈ {𝑦𝜓})
2 nfsbcdw.2 . . 3 (𝜑𝑥𝐴)
3 nfsbcdw.1 . . . 4 𝑦𝜑
4 nfsbcdw.3 . . . 4 (𝜑 → Ⅎ𝑥𝜓)
53, 4nfabdw 2368 . . 3 (𝜑𝑥{𝑦𝜓})
62, 5nfeld 2365 . 2 (𝜑 → Ⅎ𝑥 𝐴 ∈ {𝑦𝜓})
71, 6nfxfrd 1499 1 (𝜑 → Ⅎ𝑥[𝐴 / 𝑦]𝜓)
Colors of variables: wff set class
Syntax hints:  wi 4  wnf 1484  wcel 2177  {cab 2192  wnfc 2336  [wsbc 3002
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-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-11 1530  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-nf 1485  df-sb 1787  df-clab 2193  df-cleq 2199  df-clel 2202  df-nfc 2338  df-sbc 3003
This theorem is referenced by:  nfsbcw  3132  nfcsbw  3134
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