Description: The absolute value of a nonzero number is nonzero. (Contributed by Mario Carneiro, 8-Sep-2014)
Ref | Expression | ||
---|---|---|---|
Hypotheses | abvf.a | |- A = ( AbsVal ` R ) |
|
abvf.b | |- B = ( Base ` R ) |
||
abveq0.z | |- .0. = ( 0g ` R ) |
||
Assertion | abvne0 | |- ( ( F e. A /\ X e. B /\ X =/= .0. ) -> ( F ` X ) =/= 0 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | abvf.a | |- A = ( AbsVal ` R ) |
|
2 | abvf.b | |- B = ( Base ` R ) |
|
3 | abveq0.z | |- .0. = ( 0g ` R ) |
|
4 | 1 2 3 | abveq0 | |- ( ( F e. A /\ X e. B ) -> ( ( F ` X ) = 0 <-> X = .0. ) ) |
5 | 4 | necon3bid | |- ( ( F e. A /\ X e. B ) -> ( ( F ` X ) =/= 0 <-> X =/= .0. ) ) |
6 | 5 | biimp3ar | |- ( ( F e. A /\ X e. B /\ X =/= .0. ) -> ( F ` X ) =/= 0 ) |