Description: Value of absolute value function. Definition 10.36 of Gleason p. 133. (Contributed by NM, 2-Oct-1999)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | absvalsqi.1 | |- A e. CC |
|
| Assertion | absval2i | |- ( abs ` A ) = ( sqrt ` ( ( ( Re ` A ) ^ 2 ) + ( ( Im ` A ) ^ 2 ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | absvalsqi.1 | |- A e. CC |
|
| 2 | absval2 | |- ( A e. CC -> ( abs ` A ) = ( sqrt ` ( ( ( Re ` A ) ^ 2 ) + ( ( Im ` A ) ^ 2 ) ) ) ) |
|
| 3 | 1 2 | ax-mp | |- ( abs ` A ) = ( sqrt ` ( ( ( Re ` A ) ^ 2 ) + ( ( Im ` A ) ^ 2 ) ) ) |