Description: Closure for the arccos function. (Contributed by Mario Carneiro, 31-Mar-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | acoscl | |- ( A e. CC -> ( arccos ` A ) e. CC ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | acosf | |- arccos : CC --> CC |
|
| 2 | 1 | ffvelcdmi | |- ( A e. CC -> ( arccos ` A ) e. CC ) |