Metamath Proof Explorer


Theorem coexd

Description: The composition of two sets is a set. (Contributed by SN, 7-Feb-2025)

Ref Expression
Hypotheses coexd.1
|- ( ph -> A e. V )
coexd.2
|- ( ph -> B e. W )
Assertion coexd
|- ( ph -> ( A o. B ) e. _V )

Proof

Step Hyp Ref Expression
1 coexd.1
 |-  ( ph -> A e. V )
2 coexd.2
 |-  ( ph -> B e. W )
3 coexg
 |-  ( ( A e. V /\ B e. W ) -> ( A o. B ) e. _V )
4 1 2 3 syl2anc
 |-  ( ph -> ( A o. B ) e. _V )