Description: Express the predicate " R is a topological ring". (Contributed by Mario Carneiro, 5-Oct-2015)
Ref | Expression | ||
---|---|---|---|
Hypotheses | istrg.1 | |
|
istdrg.1 | |
||
Assertion | istdrg | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | istrg.1 | |
|
2 | istdrg.1 | |
|
3 | elin | |
|
4 | 3 | anbi1i | |
5 | fveq2 | |
|
6 | 5 1 | eqtr4di | |
7 | fveq2 | |
|
8 | 7 2 | eqtr4di | |
9 | 6 8 | oveq12d | |
10 | 9 | eleq1d | |
11 | df-tdrg | |
|
12 | 10 11 | elrab2 | |
13 | df-3an | |
|
14 | 4 12 13 | 3bitr4i | |