Metamath Proof Explorer


Theorem divne0

Description: The ratio of nonzero numbers is nonzero. (Contributed by NM, 28-Dec-2007)

Ref Expression
Assertion divne0
|- ( ( ( A e. CC /\ A =/= 0 ) /\ ( B e. CC /\ B =/= 0 ) ) -> ( A / B ) =/= 0 )

Proof

Step Hyp Ref Expression
1 divne0b
 |-  ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> ( A =/= 0 <-> ( A / B ) =/= 0 ) )
2 1 3expb
 |-  ( ( A e. CC /\ ( B e. CC /\ B =/= 0 ) ) -> ( A =/= 0 <-> ( A / B ) =/= 0 ) )
3 2 biimpa
 |-  ( ( ( A e. CC /\ ( B e. CC /\ B =/= 0 ) ) /\ A =/= 0 ) -> ( A / B ) =/= 0 )
4 3 an32s
 |-  ( ( ( A e. CC /\ A =/= 0 ) /\ ( B e. CC /\ B =/= 0 ) ) -> ( A / B ) =/= 0 )