Theorem gencbvex2 3151

Description: Restatement of gencbvex 3150 with weaker hypotheses. (Contributed by Jeff Hankins, 6-Dec-2006.)

Hypotheses

Ref	Expression
gencbvex2.1	|- A e. _V
gencbvex2.2	|- ( A = y -> ( ph <-> ps ) )
gencbvex2.3	|- ( A = y -> ( ch <-> th ) )
gencbvex2.4	|- ( th -> E. x ( ch /\ A = y ) )

Assertion

Ref	Expression
gencbvex2	|- ( E. x ( ch /\ ph ) <-> E. y ( th /\ ps ) )

Distinct variable groups:   ps, x   ph, y   th, x   ch, y   y, A

Allowed substitution hints:   ph( x)   ps( y)   ch( x)   th( y)   A( x)

Proof of Theorem gencbvex2

Step	Hyp	Ref	Expression
1		gencbvex2.1	. 2 |- A e. _V
2		gencbvex2.2	. 2 |- ( A = y -> ( ph <-> ps ) )
3		gencbvex2.3	. 2 |- ( A = y -> ( ch <-> th ) )
4		gencbvex2.4	. . 3 |- ( th -> E. x ( ch /\ A = y ) )
5	3	biimpac 484	. . . 4 |- ( ( ch /\ A = y ) -> th )
6	5	exlimiv 1727	. . 3 |- ( E. x ( ch /\ A = y ) -> th )
7	4, 6	impbii 188	. 2 |- ( th <-> E. x ( ch /\ A = y ) )
8	1, 2, 3, 7	gencbvex 3150	1 |- ( E. x ( ch /\ ph ) <-> E. y ( th /\ ps ) )

Syntax hints:   -> wi 4   <-> wb 184   /\ wa 367   = wceq 1398   E.wex 1617   e. wcel 1823   _Vcvv 3106

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1623  ax-4 1636  ax-5 1709  ax-6 1752  ax-7 1795  ax-10 1842  ax-11 1847  ax-12 1859  ax-ext 2432

This theorem depends on definitions:  df-bi 185  df-an 369  df-tru 1401  df-ex 1618  df-nf 1622  df-sb 1745  df-clab 2440  df-cleq 2446  df-clel 2449  df-v 3108

This theorem is referenced by: (None)