Description: _i is not 1. (Contributed by SN, 25-Apr-2025)
Ref | Expression | ||
---|---|---|---|
Assertion | ine1 | |- _i =/= 1 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 1re | |- 1 e. RR |
|
2 | inelr | |- -. _i e. RR |
|
3 | nelne2 | |- ( ( 1 e. RR /\ -. _i e. RR ) -> 1 =/= _i ) |
|
4 | 1 2 3 | mp2an | |- 1 =/= _i |
5 | 4 | necomi | |- _i =/= 1 |