Description: Version of equs4v with its consequence simplified by exsimpr . (Contributed by BJ, 9-Nov-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | alequexv | |- ( A. x ( x = y -> ph ) -> E. x ph ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ax6ev | |- E. x x = y |
|
| 2 | exim | |- ( A. x ( x = y -> ph ) -> ( E. x x = y -> E. x ph ) ) |
|
| 3 | 1 2 | mpi | |- ( A. x ( x = y -> ph ) -> E. x ph ) |