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Theorem dedhb 2820
Description: A deduction theorem for converting the inference 𝑥𝐴 => 𝜑 into a closed theorem. Use nfa1 1502 and nfab 2258 to eliminate the hypothesis of the substitution instance 𝜓 of the inference. For converting the inference form into a deduction form, abidnf 2819 is useful. (Contributed by NM, 8-Dec-2006.)
Hypotheses
Ref Expression
dedhb.1 (𝐴 = {𝑧 ∣ ∀𝑥 𝑧𝐴} → (𝜑𝜓))
dedhb.2 𝜓
Assertion
Ref Expression
dedhb (𝑥𝐴𝜑)
Distinct variable groups:   𝑥,𝑧   𝑧,𝐴
Allowed substitution hints:   𝜑(𝑥,𝑧)   𝜓(𝑥,𝑧)   𝐴(𝑥)

Proof of Theorem dedhb
StepHypRef Expression
1 dedhb.2 . 2 𝜓
2 abidnf 2819 . . . 4 (𝑥𝐴 → {𝑧 ∣ ∀𝑥 𝑧𝐴} = 𝐴)
32eqcomd 2118 . . 3 (𝑥𝐴𝐴 = {𝑧 ∣ ∀𝑥 𝑧𝐴})
4 dedhb.1 . . 3 (𝐴 = {𝑧 ∣ ∀𝑥 𝑧𝐴} → (𝜑𝜓))
53, 4syl 14 . 2 (𝑥𝐴 → (𝜑𝜓))
61, 5mpbiri 167 1 (𝑥𝐴𝜑)
Colors of variables: wff set class
Syntax hints:  wi 4  wb 104  wal 1310   = wceq 1312  wcel 1461  {cab 2099  wnfc 2240
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-5 1404  ax-7 1405  ax-gen 1406  ax-ie1 1450  ax-ie2 1451  ax-8 1463  ax-11 1465  ax-4 1468  ax-17 1487  ax-i9 1491  ax-ial 1495  ax-i5r 1496  ax-ext 2095
This theorem depends on definitions:  df-bi 116  df-nf 1418  df-sb 1717  df-clab 2100  df-cleq 2106  df-clel 2109  df-nfc 2242
This theorem is referenced by: (None)
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