Description: The multiplication operation of the ring of integers. (Contributed by Thierry Arnoux, 1-Nov-2017) (Revised by AV, 9-Jun-2019)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | zringmulr | |- x. = ( .r ` ZZring ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | zex | |- ZZ e. _V |
|
| 2 | df-zring | |- ZZring = ( CCfld |`s ZZ ) |
|
| 3 | cnfldmul | |- x. = ( .r ` CCfld ) |
|
| 4 | 2 3 | ressmulr | |- ( ZZ e. _V -> x. = ( .r ` ZZring ) ) |
| 5 | 1 4 | ax-mp | |- x. = ( .r ` ZZring ) |