Description: Deduction quantifying both antecedent and consequent, based on Theorem 19.22 of Margaris p. 90. (Contributed by NM, 17-Sep-2003)
Ref | Expression | ||
---|---|---|---|
Hypothesis | reximdv2.1 | |- ( ph -> ( ( x e. A /\ ps ) -> ( x e. B /\ ch ) ) ) |
|
Assertion | reximdv2 | |- ( ph -> ( E. x e. A ps -> E. x e. B ch ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | reximdv2.1 | |- ( ph -> ( ( x e. A /\ ps ) -> ( x e. B /\ ch ) ) ) |
|
2 | 1 | eximdv | |- ( ph -> ( E. x ( x e. A /\ ps ) -> E. x ( x e. B /\ ch ) ) ) |
3 | df-rex | |- ( E. x e. A ps <-> E. x ( x e. A /\ ps ) ) |
|
4 | df-rex | |- ( E. x e. B ch <-> E. x ( x e. B /\ ch ) ) |
|
5 | 2 3 4 | 3imtr4g | |- ( ph -> ( E. x e. A ps -> E. x e. B ch ) ) |