Theorem elab3g 2889

Description: Membership in a class abstraction, with a weaker antecedent than elabg 2884. (Contributed by NM, 29-Aug-2006.)

Hypothesis

Ref	Expression
elab3g.1	|- ( x = A -> ( ph <-> ps ) )

Assertion

Ref	Expression
elab3g	|- ( ( ps -> A e. B ) -> ( A e. { x | ph } <-> ps ) )

Distinct variable groups:   ps, x   x, A

Allowed substitution hints:   ph( x)   B( x)

Proof of Theorem elab3g

Step	Hyp	Ref	Expression
1		nfcv 2319	. 2 |- F/_ x A
2		nfv 1528	. 2 |- F/ x ps
3		elab3g.1	. 2 |- ( x = A -> ( ph <-> ps ) )
4	1, 2, 3	elab3gf 2888	1 |- ( ( ps -> A e. B ) -> ( A e. { x | ph } <-> ps ) )

Syntax hints:   -> wi 4   <-> wb 105   = wceq 1353   e. wcel 2148   {cab 2163

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-io 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159

This theorem depends on definitions:  df-bi 117  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-v 2740

This theorem is referenced by:  elab3  2890  elssabg  4149  elrnmptg  4880  elrelimasn  4995  fvelrnb  5564  elmapg  6661