Metamath Proof Explorer


Theorem iscnrm3rlem6

Description: Lemma for iscnrm3rlem7 . (Contributed by Zhi Wang, 5-Sep-2024)

Ref Expression
Hypotheses iscnrm3rlem4.1
|- ( ph -> J e. Top )
iscnrm3rlem4.2
|- ( ph -> S C_ U. J )
iscnrm3rlem5.3
|- ( ph -> T C_ U. J )
iscnrm3rlem6.4
|- ( ph -> O C_ ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) )
Assertion iscnrm3rlem6
|- ( ph -> ( O e. ( J |`t ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) ) <-> O e. J ) )

Proof

Step Hyp Ref Expression
1 iscnrm3rlem4.1
 |-  ( ph -> J e. Top )
2 iscnrm3rlem4.2
 |-  ( ph -> S C_ U. J )
3 iscnrm3rlem5.3
 |-  ( ph -> T C_ U. J )
4 iscnrm3rlem6.4
 |-  ( ph -> O C_ ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) )
5 1 2 3 iscnrm3rlem5
 |-  ( ph -> ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) e. J )
6 restopn2
 |-  ( ( J e. Top /\ ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) e. J ) -> ( O e. ( J |`t ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) ) <-> ( O e. J /\ O C_ ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) ) ) )
7 1 5 6 syl2anc
 |-  ( ph -> ( O e. ( J |`t ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) ) <-> ( O e. J /\ O C_ ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) ) ) )
8 4 7 mpbiran2d
 |-  ( ph -> ( O e. ( J |`t ( U. J \ ( ( ( cls ` J ) ` S ) i^i ( ( cls ` J ) ` T ) ) ) ) <-> O e. J ) )