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Theorem nfcsbw 3121
Description: Bound-variable hypothesis builder for substitution into a class. Version of nfcsb 3122 with a disjoint variable condition. (Contributed by Mario Carneiro, 12-Oct-2016.) (Revised by GG, 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 3085 . . 3 𝐴 / 𝑦𝐵 = {𝑧[𝐴 / 𝑦]𝑧𝐵}
2 nftru 1480 . . . 4 𝑧
3 nftru 1480 . . . . 5 𝑦
4 nfcsbw.1 . . . . . 6 𝑥𝐴
54a1i 9 . . . . 5 (⊤ → 𝑥𝐴)
6 nfcsbw.2 . . . . . . 7 𝑥𝐵
76a1i 9 . . . . . 6 (⊤ → 𝑥𝐵)
87nfcrd 2353 . . . . 5 (⊤ → Ⅎ𝑥 𝑧𝐵)
93, 5, 8nfsbcdw 3118 . . . 4 (⊤ → Ⅎ𝑥[𝐴 / 𝑦]𝑧𝐵)
102, 9nfabdw 2358 . . 3 (⊤ → 𝑥{𝑧[𝐴 / 𝑦]𝑧𝐵})
111, 10nfcxfrd 2337 . 2 (⊤ → 𝑥𝐴 / 𝑦𝐵)
1211mptru 1373 1 𝑥𝐴 / 𝑦𝐵
Colors of variables: wff set class
Syntax hints:  wtru 1365  wcel 2167  {cab 2182  wnfc 2326  [wsbc 2989  csb 3084
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 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-11 1520  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-ext 2178
This theorem depends on definitions:  df-bi 117  df-tru 1367  df-nf 1475  df-sb 1777  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-sbc 2990  df-csb 3085
This theorem is referenced by:  fvmpopr2d  6059  elovmporab1w  6124  fprod2dlemstep  11787  fprodcom2fi  11791  dvmptfsum  14961
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