Description: Restrictions of a collection of ordered pairs of related elements are sets. (Contributed by Alexander van der Vekens, 1-Nov-2017) (Revised by AV, 15-Jan-2021)
Ref | Expression | ||
---|---|---|---|
Hypotheses | opabresex2d.1 | |- ( ( ph /\ x ( W ` G ) y ) -> ps ) |
|
opabresex2d.2 | |- ( ph -> { <. x , y >. | ps } e. V ) |
||
Assertion | opabresex2d | |- ( ph -> { <. x , y >. | ( x ( W ` G ) y /\ th ) } e. _V ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | opabresex2d.1 | |- ( ( ph /\ x ( W ` G ) y ) -> ps ) |
|
2 | opabresex2d.2 | |- ( ph -> { <. x , y >. | ps } e. V ) |
|
3 | 1 | ex | |- ( ph -> ( x ( W ` G ) y -> ps ) ) |
4 | 3 | alrimivv | |- ( ph -> A. x A. y ( x ( W ` G ) y -> ps ) ) |
5 | opabbrex | |- ( ( A. x A. y ( x ( W ` G ) y -> ps ) /\ { <. x , y >. | ps } e. V ) -> { <. x , y >. | ( x ( W ` G ) y /\ th ) } e. _V ) |
|
6 | 4 2 5 | syl2anc | |- ( ph -> { <. x , y >. | ( x ( W ` G ) y /\ th ) } e. _V ) |