Description: A complex number times its conjugate is real. (Contributed by NM, 11-May-1999)
Ref | Expression | ||
---|---|---|---|
Hypothesis | recl.1 | |- A e. CC |
|
Assertion | cjmulrcli | |- ( A x. ( * ` A ) ) e. RR |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | recl.1 | |- A e. CC |
|
2 | cjmulrcl | |- ( A e. CC -> ( A x. ( * ` A ) ) e. RR ) |
|
3 | 1 2 | ax-mp | |- ( A x. ( * ` A ) ) e. RR |