Description: The logarithm of a nonzero complex number is a complex number. Deduction form of logcl . (Contributed by David Moews, 28-Feb-2017)
Ref | Expression | ||
---|---|---|---|
Hypotheses | logcld.1 | |- ( ph -> X e. CC ) |
|
logcld.2 | |- ( ph -> X =/= 0 ) |
||
Assertion | logcld | |- ( ph -> ( log ` X ) e. CC ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | logcld.1 | |- ( ph -> X e. CC ) |
|
2 | logcld.2 | |- ( ph -> X =/= 0 ) |
|
3 | logcl | |- ( ( X e. CC /\ X =/= 0 ) -> ( log ` X ) e. CC ) |
|
4 | 1 2 3 | syl2anc | |- ( ph -> ( log ` X ) e. CC ) |