Theorem ralnex2 2609

Description: Relationship between two restricted universal and existential quantifiers. (Contributed by Glauco Siliprandi, 11-Dec-2019.) (Proof shortened by Wolf Lammen, 18-May-2023.)

Assertion

Ref	Expression
ralnex2	|- ( A. x e. A A. y e. B -. ph <-> -. E. x e. A E. y e. B ph )

Proof of Theorem ralnex2

Step	Hyp	Ref	Expression
1		ralnex 2458	. . 3 |- ( A. y e. B -. ph <-> -. E. y e. B ph )
2	1	ralbii 2476	. 2 |- ( A. x e. A A. y e. B -. ph <-> A. x e. A -. E. y e. B ph )
3		ralnex 2458	. 2 |- ( A. x e. A -. E. y e. B ph <-> -. E. x e. A E. y e. B ph )
4	2, 3	bitri 183	1 |- ( A. x e. A A. y e. B -. ph <-> -. E. x e. A E. y e. B ph )

Syntax hints:   -. wn 3   <-> wb 104   A.wral 2448   E.wrex 2449

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 609  ax-in2 610  ax-5 1440  ax-gen 1442  ax-ie2 1487  ax-4 1503  ax-17 1519

This theorem depends on definitions:  df-bi 116  df-tru 1351  df-fal 1354  df-nf 1454  df-ral 2453  df-rex 2454

This theorem is referenced by: (None)