Metamath Proof Explorer


Theorem fnopab

Description: Functionality and domain of an ordered-pair class abstraction. (Contributed by NM, 5-Mar-1996)

Ref Expression
Hypotheses fnopab.1
|- ( x e. A -> E! y ph )
fnopab.2
|- F = { <. x , y >. | ( x e. A /\ ph ) }
Assertion fnopab
|- F Fn A

Proof

Step Hyp Ref Expression
1 fnopab.1
 |-  ( x e. A -> E! y ph )
2 fnopab.2
 |-  F = { <. x , y >. | ( x e. A /\ ph ) }
3 1 rgen
 |-  A. x e. A E! y ph
4 2 fnopabg
 |-  ( A. x e. A E! y ph <-> F Fn A )
5 3 4 mpbi
 |-  F Fn A