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 ) |
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 ) |