Description: The imaginary part of a complex number is real (closure law). (Contributed by NM, 11-May-1999)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | recl.1 | |- A e. CC |
|
| Assertion | imcli | |- ( Im ` A ) e. RR |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | recl.1 | |- A e. CC |
|
| 2 | imcl | |- ( A e. CC -> ( Im ` A ) e. RR ) |
|
| 3 | 1 2 | ax-mp | |- ( Im ` A ) e. RR |