Theorem vdif0im 3309

Description: Universal class equality in terms of empty difference. (Contributed by Jim Kingdon, 3-Aug-2018.)

Assertion

Ref	Expression
vdif0im	|- ( A = _V -> ( _V \ A ) = (/) )

Proof of Theorem vdif0im

Step	Hyp	Ref	Expression
1		vss 3291	. 2 |- ( _V C_ A <-> A = _V )
2		ssdif0im 3308	. 2 |- ( _V C_ A -> ( _V \ A ) = (/) )
3	1, 2	sylbir 133	1 |- ( A = _V -> ( _V \ A ) = (/) )

Syntax hints:   -> wi 4   = wceq 1284   _Vcvv 2601   \ cdif 2970   C_ wss 2973   (/)c0 3251

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-in1 576  ax-in2 577  ax-io 662  ax-5 1376  ax-7 1377  ax-gen 1378  ax-ie1 1422  ax-ie2 1423  ax-8 1435  ax-10 1436  ax-11 1437  ax-i12 1438  ax-bndl 1439  ax-4 1440  ax-17 1459  ax-i9 1463  ax-ial 1467  ax-i5r 1468  ax-ext 2063

This theorem depends on definitions:  df-bi 115  df-tru 1287  df-nf 1390  df-sb 1686  df-clab 2068  df-cleq 2074  df-clel 2077  df-nfc 2208  df-v 2603  df-dif 2975  df-in 2979  df-ss 2986  df-nul 3252

This theorem is referenced by: (None)