Metamath Proof Explorer


Theorem elpwincl1

Description: Closure of intersection with regard to elementhood to a power set. (Contributed by Thierry Arnoux, 18-May-2020)

Ref Expression
Hypothesis elpwincl.1
|- ( ph -> A e. ~P C )
Assertion elpwincl1
|- ( ph -> ( A i^i B ) e. ~P C )

Proof

Step Hyp Ref Expression
1 elpwincl.1
 |-  ( ph -> A e. ~P C )
2 elpwi
 |-  ( A e. ~P C -> A C_ C )
3 ssinss1
 |-  ( A C_ C -> ( A i^i B ) C_ C )
4 1 2 3 3syl
 |-  ( ph -> ( A i^i B ) C_ C )
5 inex1g
 |-  ( A e. ~P C -> ( A i^i B ) e. _V )
6 elpwg
 |-  ( ( A i^i B ) e. _V -> ( ( A i^i B ) e. ~P C <-> ( A i^i B ) C_ C ) )
7 1 5 6 3syl
 |-  ( ph -> ( ( A i^i B ) e. ~P C <-> ( A i^i B ) C_ C ) )
8 4 7 mpbird
 |-  ( ph -> ( A i^i B ) e. ~P C )