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 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | zex | |
|
2 | df-zring | |
|
3 | cnfldmul | |
|
4 | 2 3 | ressmulr | |
5 | 1 4 | ax-mp | |