Theorem neneqad 2324

Description: If it is not the case that two classes are equal, they are unequal. Converse of neneqd 2266. One-way deduction form of df-ne 2246. (Contributed by David Moews, 28-Feb-2017.)

Hypothesis

Ref	Expression
neneqad.1	|- ( ph -> -. A = B )

Assertion

Ref	Expression
neneqad	|- ( ph -> A =/= B )

Proof of Theorem neneqad

Step	Hyp	Ref	Expression
1		neneqad.1	. . 3 |- ( ph -> -. A = B )
2	1	con2i 589	. 2 |- ( A = B -> -. ph )
3	2	necon2ai 2299	1 |- ( ph -> A =/= B )

Syntax hints:   -. wn 3   -> wi 4   = wceq 1284   =/= wne 2245

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

This theorem depends on definitions:  df-bi 115  df-ne 2246

This theorem is referenced by:  ne0i  3257  nsuceq0g  4173  fidifsnen  6355  nqnq0pi  6628  xrlttri3  8872  expival  9478