Metamath Proof Explorer
Description: Closure of the natural logarithm function. (Contributed by NM, 21-Apr-2008) (Revised by Mario Carneiro, 23-Sep-2014)
|
|
Ref |
Expression |
|
Assertion |
logcl |
⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐴 ≠ 0 ) → ( log ‘ 𝐴 ) ∈ ℂ ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
logrncl |
⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐴 ≠ 0 ) → ( log ‘ 𝐴 ) ∈ ran log ) |
2 |
|
logrncn |
⊢ ( ( log ‘ 𝐴 ) ∈ ran log → ( log ‘ 𝐴 ) ∈ ℂ ) |
3 |
1 2
|
syl |
⊢ ( ( 𝐴 ∈ ℂ ∧ 𝐴 ≠ 0 ) → ( log ‘ 𝐴 ) ∈ ℂ ) |