Theorem elab2g 2740

Description: Membership in a class abstraction, using implicit substitution. (Contributed by NM, 13-Sep-1995.)

Hypotheses

Ref	Expression
elab2g.1	⊢ (𝑥 = 𝐴 → (𝜑 ↔ 𝜓))
elab2g.2	⊢ 𝐵 = {𝑥 ∣ 𝜑}

Assertion

Ref	Expression
elab2g	⊢ (𝐴 ∈ 𝑉 → (𝐴 ∈ 𝐵 ↔ 𝜓))

Distinct variable groups:   𝜓,𝑥   𝑥,𝐴

Allowed substitution hints:   𝜑(𝑥)   𝐵(𝑥)   𝑉(𝑥)

Proof of Theorem elab2g

Step	Hyp	Ref	Expression
1		elab2g.2	. . 3 ⊢ 𝐵 = {𝑥 ∣ 𝜑}
2	1	eleq2i 2145	. 2 ⊢ (𝐴 ∈ 𝐵 ↔ 𝐴 ∈ {𝑥 ∣ 𝜑})
3		elab2g.1	. . 3 ⊢ (𝑥 = 𝐴 → (𝜑 ↔ 𝜓))
4	3	elabg 2739	. 2 ⊢ (𝐴 ∈ 𝑉 → (𝐴 ∈ {𝑥 ∣ 𝜑} ↔ 𝜓))
5	2, 4	syl5bb 190	1 ⊢ (𝐴 ∈ 𝑉 → (𝐴 ∈ 𝐵 ↔ 𝜓))

Syntax hints:   → wi 4   ↔ wb 103   = wceq 1284   ∈ wcel 1433  {cab 2067

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-io 662  ax-5 1376  ax-7 1377  ax-gen 1378  ax-ie1 1422  ax-ie2 1423  ax-8 1435  ax-10 1436  ax-11 1437  ax-i12 1438  ax-bndl 1439  ax-4 1440  ax-17 1459  ax-i9 1463  ax-ial 1467  ax-i5r 1468  ax-ext 2063

This theorem depends on definitions:  df-bi 115  df-tru 1287  df-nf 1390  df-sb 1686  df-clab 2068  df-cleq 2074  df-clel 2077  df-nfc 2208  df-v 2603

This theorem is referenced by:  elab2  2741  elab4g  2742  eldif  2982  elun  3113  elin  3155  elsng  3413  elprg  3418  eluni  3604  eliun  3682  eliin  3683  elopab  4013  elong  4128  opeliunxp  4413  elrn2g  4543  eldmg  4548  elrnmpt  4601  elrnmpt1  4603  elimag  4692  elrnmpt2g  5633  eloprabi  5842  tfrlem3ag  5947  elqsg  6179  1idprl  6780  1idpru  6781  recexprlemell  6812  recexprlemelu  6813