Description: Obsolete version of rexn0 as of 2-Sep-2024. (Contributed by Szymon Jaroszewicz, 3-Apr-2007) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | rexn0OLD | |- ( E. x e. A ph -> A =/= (/) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ne0i | |- ( x e. A -> A =/= (/) ) |
|
| 2 | 1 | a1d | |- ( x e. A -> ( ph -> A =/= (/) ) ) |
| 3 | 2 | rexlimiv | |- ( E. x e. A ph -> A =/= (/) ) |