Theorem nfra2xy 2499

Description: Not-free given two restricted quantifiers. (Contributed by Jim Kingdon, 20-Aug-2018.)

Assertion

Ref	Expression
nfra2xy	|- F/ y A. x e. A A. y e. B ph

Distinct variable groups:   x, y   y, A

Allowed substitution hints:   ph( x, y)   A( x)   B( x, y)

Proof of Theorem nfra2xy

Step	Hyp	Ref	Expression
1		nfcv 2299	. 2 |- F/_ y A
2		nfra1 2488	. 2 |- F/ y A. y e. B ph
3	1, 2	nfralxy 2495	1 |- F/ y A. x e. A A. y e. B ph

Syntax hints:   F/wnf 1440   A.wral 2435

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-5 1427  ax-7 1428  ax-gen 1429  ax-ie1 1473  ax-ie2 1474  ax-4 1490  ax-17 1506  ax-ial 1514  ax-i5r 1515  ax-ext 2139

This theorem depends on definitions:  df-bi 116  df-tru 1338  df-nf 1441  df-cleq 2150  df-clel 2153  df-nfc 2288  df-ral 2440

This theorem is referenced by:  invdisj  3959  reusv3  4418