Description: Apply a choice equivalent. (Contributed by Mario Carneiro, 17-May-2015)
Ref | Expression | ||
---|---|---|---|
Hypothesis | axaci.1 | |- ( CHOICE <-> A. x ph ) |
|
Assertion | axaci | |- ph |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | axaci.1 | |- ( CHOICE <-> A. x ph ) |
|
2 | axac3 | |- CHOICE |
|
3 | 2 1 | mpbi | |- A. x ph |
4 | 3 | spi | |- ph |