Description: Closure of the sine function. (Contributed by Mario Carneiro, 29-May-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | sincld.1 | |- ( ph -> A e. CC ) | |
| Assertion | sincld | |- ( ph -> ( sin ` A ) e. CC ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | sincld.1 | |- ( ph -> A e. CC ) | |
| 2 | sincl | |- ( A e. CC -> ( sin ` A ) e. CC ) | |
| 3 | 1 2 | syl | |- ( ph -> ( sin ` A ) e. CC ) |