Description: A number is nonzero iff its complex conjugate is nonzero. (Contributed by Mario Carneiro, 29-May-2016)
Ref | Expression | ||
---|---|---|---|
Hypotheses | recld.1 | |- ( ph -> A e. CC ) |
|
cjne0d.2 | |- ( ph -> A =/= 0 ) |
||
Assertion | cjne0d | |- ( ph -> ( * ` A ) =/= 0 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | recld.1 | |- ( ph -> A e. CC ) |
|
2 | cjne0d.2 | |- ( ph -> A =/= 0 ) |
|
3 | cjne0 | |- ( A e. CC -> ( A =/= 0 <-> ( * ` A ) =/= 0 ) ) |
|
4 | 1 3 | syl | |- ( ph -> ( A =/= 0 <-> ( * ` A ) =/= 0 ) ) |
5 | 2 4 | mpbid | |- ( ph -> ( * ` A ) =/= 0 ) |