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Theorem nfcsbw 3081
Description: Bound-variable hypothesis builder for substitution into a class. Version of nfcsb 3082 with a disjoint variable condition. (Contributed by Mario Carneiro, 12-Oct-2016.) (Revised by Gino Giotto, 10-Jan-2024.)
Hypotheses
Ref Expression
nfcsbw.1 𝑥𝐴
nfcsbw.2 𝑥𝐵
Assertion
Ref Expression
nfcsbw 𝑥𝐴 / 𝑦𝐵
Distinct variable group:   𝑥,𝑦
Allowed substitution hints:   𝐴(𝑥,𝑦)   𝐵(𝑥,𝑦)

Proof of Theorem nfcsbw
Dummy variable 𝑧 is distinct from all other variables.
StepHypRef Expression
1 df-csb 3046 . . 3 𝐴 / 𝑦𝐵 = {𝑧[𝐴 / 𝑦]𝑧𝐵}
2 nftru 1454 . . . 4 𝑧
3 nftru 1454 . . . . 5 𝑦
4 nfcsbw.1 . . . . . 6 𝑥𝐴
54a1i 9 . . . . 5 (⊤ → 𝑥𝐴)
6 nfcsbw.2 . . . . . . 7 𝑥𝐵
76a1i 9 . . . . . 6 (⊤ → 𝑥𝐵)
87nfcrd 2322 . . . . 5 (⊤ → Ⅎ𝑥 𝑧𝐵)
93, 5, 8nfsbcdw 3079 . . . 4 (⊤ → Ⅎ𝑥[𝐴 / 𝑦]𝑧𝐵)
102, 9nfabdw 2327 . . 3 (⊤ → 𝑥{𝑧[𝐴 / 𝑦]𝑧𝐵})
111, 10nfcxfrd 2306 . 2 (⊤ → 𝑥𝐴 / 𝑦𝐵)
1211mptru 1352 1 𝑥𝐴 / 𝑦𝐵
Colors of variables: wff set class
Syntax hints:  wtru 1344  wcel 2136  {cab 2151  wnfc 2295  [wsbc 2951  csb 3045
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-11 1494  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147
This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-sbc 2952  df-csb 3046
This theorem is referenced by:  fprod2dlemstep  11563  fprodcom2fi  11567
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