Description: Relationship between the natural logarithm function and the exponential function. (Contributed by Mario Carneiro, 29-May-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | relogcld.1 | |- ( ph -> A e. RR+ ) |
|
| Assertion | reeflogd | |- ( ph -> ( exp ` ( log ` A ) ) = A ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | relogcld.1 | |- ( ph -> A e. RR+ ) |
|
| 2 | reeflog | |- ( A e. RR+ -> ( exp ` ( log ` A ) ) = A ) |
|
| 3 | 1 2 | syl | |- ( ph -> ( exp ` ( log ` A ) ) = A ) |