Theorem rexex 2554

Description: Restricted existence implies existence. (Contributed by NM, 11-Nov-1995.)

Assertion

Ref	Expression
rexex	|- ( E. x e. A ph -> E. x ph )

Proof of Theorem rexex

Step	Hyp	Ref	Expression
1		df-rex 2492	. 2 |- ( E. x e. A ph <-> E. x ( x e. A /\ ph ) )
2		simpr 110	. . 3 |- ( ( x e. A /\ ph ) -> ph )
3	2	eximi 1624	. 2 |- ( E. x ( x e. A /\ ph ) -> E. x ph )
4	1, 3	sylbi 121	1 |- ( E. x e. A ph -> E. x ph )

Syntax hints:   -> wi 4   /\ wa 104   E.wex 1516   e. wcel 2178   E.wrex 2487

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 1471  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-4 1534  ax-ial 1558

This theorem depends on definitions:  df-bi 117  df-rex 2492

This theorem is referenced by:  reu3  2970  rmo2i  3097  dffo5  5752  halfnq  7559  nsmallnq  7561  0npr  7631  genpml  7665  genpmu  7666  ltexprlemm  7748  ltexprlemloc  7755  dedekindeulemlub  15207  dedekindicclemlub  15216