Description: The real part of _i . (Contributed by Scott Fenton, 9-Jun-2006)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rei | |- ( Re ` _i ) = 0 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ax-icn | |- _i e. CC |
|
| 2 | ax-1cn | |- 1 e. CC |
|
| 3 | 1 2 | mulcli | |- ( _i x. 1 ) e. CC |
| 4 | 3 | addlidi | |- ( 0 + ( _i x. 1 ) ) = ( _i x. 1 ) |
| 5 | 4 | fveq2i | |- ( Re ` ( 0 + ( _i x. 1 ) ) ) = ( Re ` ( _i x. 1 ) ) |
| 6 | 0re | |- 0 e. RR |
|
| 7 | 1re | |- 1 e. RR |
|
| 8 | crre | |- ( ( 0 e. RR /\ 1 e. RR ) -> ( Re ` ( 0 + ( _i x. 1 ) ) ) = 0 ) |
|
| 9 | 6 7 8 | mp2an | |- ( Re ` ( 0 + ( _i x. 1 ) ) ) = 0 |
| 10 | 1 | mulridi | |- ( _i x. 1 ) = _i |
| 11 | 10 | fveq2i | |- ( Re ` ( _i x. 1 ) ) = ( Re ` _i ) |
| 12 | 5 9 11 | 3eqtr3ri | |- ( Re ` _i ) = 0 |