Description: Formula-building rule for restricted quantifiers (deduction form). (Contributed by NM, 28-Jan-2006)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | 2ralbidv.1 | |- ( ph -> ( ps <-> ch ) ) |
|
| Assertion | rexralbidv | |- ( ph -> ( E. x e. A A. y e. B ps <-> E. x e. A A. y e. B ch ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 2ralbidv.1 | |- ( ph -> ( ps <-> ch ) ) |
|
| 2 | 1 | ralbidv | |- ( ph -> ( A. y e. B ps <-> A. y e. B ch ) ) |
| 3 | 2 | rexbidv | |- ( ph -> ( E. x e. A A. y e. B ps <-> E. x e. A A. y e. B ch ) ) |