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Theorem nfcsbd 3183
Description: Deduction version of nfcsb 3185. (Contributed by NM, 21-Nov-2005.) (Revised by Mario Carneiro, 12-Oct-2016.)
Hypotheses
Ref Expression
nfcsbd.1 Ⅎ𝑦𝜑
nfcsbd.2 (𝜑 → Ⅎ𝑥𝐴)
nfcsbd.3 (𝜑 → Ⅎ𝑥𝐵)
Assertion
Ref Expression
nfcsbd (𝜑 → Ⅎ𝑥⦋𝐴 / 𝑦⦌𝐵)

Proof of Theorem nfcsbd
Dummy variable 𝑧 is distinct from all other variables.
StepHypRef Expression
1 df-csb 3148 . 2 ⦋𝐴 / 𝑦⦌𝐵 = {𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝐵}
2 nfv 1581 . . 3 Ⅎ𝑧𝜑
3 nfcsbd.1 . . . 4 Ⅎ𝑦𝜑
4 nfcsbd.2 . . . 4 (𝜑 → Ⅎ𝑥𝐴)
5 nfcsbd.3 . . . . 5 (𝜑 → Ⅎ𝑥𝐵)
65nfcrd 2406 . . . 4 (𝜑 → Ⅎ𝑥 𝑧 ∈ 𝐵)
73, 4, 6nfsbcd 3071 . . 3 (𝜑 → Ⅎ𝑥[𝐴 / 𝑦]𝑧 ∈ 𝐵)
82, 7nfabd 2412 . 2 (𝜑 → Ⅎ𝑥{𝑧 ∣ [𝐴 / 𝑦]𝑧 ∈ 𝐵})
91, 8nfcxfrd 2390 1 (𝜑 → Ⅎ𝑥⦋𝐴 / 𝑦⦌𝐵)
Colors of variables:    wff set class
This proof depends on syntax axioms:   → wi 4  Ⅎwnf 1513   ∈ wcel 2209  {cab 2224  Ⅎwnfc 2379  [wsbc 3051  ⦋csb 3147
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220
This proof depends on definitions:  df-bi 117  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-sbc 3052  df-csb 3148
This theorem is used by:  nfcsb  3185
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