Description: ( 2 x. _i ) =/= 0 . (Contributed by David A. Wheeler, 8-Dec-2018)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 2muline0 | |- ( 2 x. _i ) =/= 0 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | 2cn | |- 2 e. CC | |
| 2 | ax-icn | |- _i e. CC | |
| 3 | 2ne0 | |- 2 =/= 0 | |
| 4 | ine0 | |- _i =/= 0 | |
| 5 | 1 2 3 4 | mulne0i | |- ( 2 x. _i ) =/= 0 |