Theorem r19.42v 2691

Description: Restricted version of Theorem 19.42 of [Margaris] p. 90. (Contributed by NM, 27-May-1998.)

Assertion

Ref	Expression
r19.42v	|- ( E. x e. A ( ph /\ ps ) <-> ( ph /\ E. x e. A ps ) )

Distinct variable group:   ph, x

Allowed substitution hints:   ps( x)   A( x)

Proof of Theorem r19.42v

Step	Hyp	Ref	Expression
1		r19.41v 2690	. 2 |- ( E. x e. A ( ps /\ ph ) <-> ( E. x e. A ps /\ ph ) )
2		ancom 266	. . 3 |- ( ( ph /\ ps ) <-> ( ps /\ ph ) )
3	2	rexbii 2540	. 2 |- ( E. x e. A ( ph /\ ps ) <-> E. x e. A ( ps /\ ph ) )
4		ancom 266	. 2 |- ( ( ph /\ E. x e. A ps ) <-> ( E. x e. A ps /\ ph ) )
5	1, 3, 4	3bitr4i 212	1 |- ( E. x e. A ( ph /\ ps ) <-> ( ph /\ E. x e. A ps ) )

Syntax hints:   /\ wa 104   <-> wb 105   E.wrex 2512

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 1496  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-4 1559  ax-17 1575  ax-ial 1583

This theorem depends on definitions:  df-bi 117  df-tru 1401  df-nf 1510  df-rex 2517

This theorem is referenced by:  ceqsrexbv  2938  ceqsrex2v  2939  2reuswapdc  3011  iunrab  4023  iunin2  4039  iundif2ss  4041  iunopab  4382  elxp2  4749  cnvuni  4922  elunirn  5917  f1oiso  5977  oprabrexex2  6301  genpdflem  7787  1idprl  7870  1idpru  7871  ltexprlemm  7880  rexuz2  9876  4fvwrd4  10437  divalgb  12566