Theorem neldifsnd 3840

Description: A is not in ( B \ { A } ). Deduction form. (Contributed by David Moews, 1-May-2017.)

Assertion

Ref	Expression
neldifsnd	|- ( ph -> -. A e. ( B \ { A } ) )

Proof of Theorem neldifsnd

Step	Hyp	Ref	Expression
1		neldifsn 3839	. 2 |- -. A e. ( B \ { A } )
2	1	a1i 9	1 |- ( ph -> -. A e. ( B \ { A } ) )

Syntax hints:   -. wn 3   -> wi 4   e. wcel 2209   \ cdif 3217   {csn 3705

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-in1 623  ax-in2 624  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220

This theorem depends on definitions:  df-bi 117  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-ne 2421  df-v 2823  df-dif 3222  df-sn 3711

This theorem is referenced by:  difsnb  3853  frirrg  4490  elirr  4683