Metamath Proof Explorer


Theorem subne0ad

Description: If the difference of two complex numbers is nonzero, they are unequal. Converse of subne0d . Contrapositive of subeq0bd . (Contributed by David Moews, 28-Feb-2017)

Ref Expression
Hypotheses negidd.1
|- ( ph -> A e. CC )
pncand.2
|- ( ph -> B e. CC )
subne0ad.3
|- ( ph -> ( A - B ) =/= 0 )
Assertion subne0ad
|- ( ph -> A =/= B )

Proof

Step Hyp Ref Expression
1 negidd.1
 |-  ( ph -> A e. CC )
2 pncand.2
 |-  ( ph -> B e. CC )
3 subne0ad.3
 |-  ( ph -> ( A - B ) =/= 0 )
4 1 2 subeq0ad
 |-  ( ph -> ( ( A - B ) = 0 <-> A = B ) )
5 4 necon3bid
 |-  ( ph -> ( ( A - B ) =/= 0 <-> A =/= B ) )
6 3 5 mpbid
 |-  ( ph -> A =/= B )