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Theorem sbcbid 2816
 Description: Formula-building deduction rule for class substitution. (Contributed by NM, 29-Dec-2014.)
Hypotheses
Ref Expression
sbcbid.1 𝑥𝜑
sbcbid.2 (𝜑 → (𝜓𝜒))
Assertion
Ref Expression
sbcbid (𝜑 → ([𝐴 / 𝑥]𝜓[𝐴 / 𝑥]𝜒))

Proof of Theorem sbcbid
StepHypRef Expression
1 sbcbid.1 . . . 4 𝑥𝜑
2 sbcbid.2 . . . 4 (𝜑 → (𝜓𝜒))
31, 2abbid 2154 . . 3 (𝜑 → {𝑥𝜓} = {𝑥𝜒})
43eleq2d 2107 . 2 (𝜑 → (𝐴 ∈ {𝑥𝜓} ↔ 𝐴 ∈ {𝑥𝜒}))
5 df-sbc 2765 . 2 ([𝐴 / 𝑥]𝜓𝐴 ∈ {𝑥𝜓})
6 df-sbc 2765 . 2 ([𝐴 / 𝑥]𝜒𝐴 ∈ {𝑥𝜒})
74, 5, 63bitr4g 212 1 (𝜑 → ([𝐴 / 𝑥]𝜓[𝐴 / 𝑥]𝜒))
 Colors of variables: wff set class Syntax hints:   → wi 4   ↔ wb 98  Ⅎwnf 1349   ∈ wcel 1393  {cab 2026  [wsbc 2764 This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-5 1336  ax-7 1337  ax-gen 1338  ax-ie1 1382  ax-ie2 1383  ax-8 1395  ax-11 1397  ax-4 1400  ax-17 1419  ax-i9 1423  ax-ial 1427  ax-i5r 1428  ax-ext 2022 This theorem depends on definitions:  df-bi 110  df-tru 1246  df-nf 1350  df-sb 1646  df-clab 2027  df-cleq 2033  df-clel 2036  df-sbc 2765 This theorem is referenced by:  sbcbidv  2817  csbeq2d  2874
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