Metamath Proof Explorer


Theorem ntrrn

Description: The range of the interior function of a topology a subset of the open sets of the topology. (Contributed by RP, 22-Apr-2021)

Ref Expression
Hypotheses ntrrn.x
|- X = U. J
ntrrn.i
|- I = ( int ` J )
Assertion ntrrn
|- ( J e. Top -> ran I C_ J )

Proof

Step Hyp Ref Expression
1 ntrrn.x
 |-  X = U. J
2 ntrrn.i
 |-  I = ( int ` J )
3 2 rneqi
 |-  ran I = ran ( int ` J )
4 vpwex
 |-  ~P s e. _V
5 4 inex2
 |-  ( J i^i ~P s ) e. _V
6 5 uniex
 |-  U. ( J i^i ~P s ) e. _V
7 6 rgenw
 |-  A. s e. ~P X U. ( J i^i ~P s ) e. _V
8 nfcv
 |-  F/_ s ~P X
9 8 fnmptf
 |-  ( A. s e. ~P X U. ( J i^i ~P s ) e. _V -> ( s e. ~P X |-> U. ( J i^i ~P s ) ) Fn ~P X )
10 7 9 mp1i
 |-  ( J e. Top -> ( s e. ~P X |-> U. ( J i^i ~P s ) ) Fn ~P X )
11 1 ntrfval
 |-  ( J e. Top -> ( int ` J ) = ( s e. ~P X |-> U. ( J i^i ~P s ) ) )
12 11 fneq1d
 |-  ( J e. Top -> ( ( int ` J ) Fn ~P X <-> ( s e. ~P X |-> U. ( J i^i ~P s ) ) Fn ~P X ) )
13 10 12 mpbird
 |-  ( J e. Top -> ( int ` J ) Fn ~P X )
14 elpwi
 |-  ( s e. ~P X -> s C_ X )
15 1 ntropn
 |-  ( ( J e. Top /\ s C_ X ) -> ( ( int ` J ) ` s ) e. J )
16 15 ex
 |-  ( J e. Top -> ( s C_ X -> ( ( int ` J ) ` s ) e. J ) )
17 14 16 syl5
 |-  ( J e. Top -> ( s e. ~P X -> ( ( int ` J ) ` s ) e. J ) )
18 17 ralrimiv
 |-  ( J e. Top -> A. s e. ~P X ( ( int ` J ) ` s ) e. J )
19 fnfvrnss
 |-  ( ( ( int ` J ) Fn ~P X /\ A. s e. ~P X ( ( int ` J ) ` s ) e. J ) -> ran ( int ` J ) C_ J )
20 13 18 19 syl2anc
 |-  ( J e. Top -> ran ( int ` J ) C_ J )
21 3 20 eqsstrid
 |-  ( J e. Top -> ran I C_ J )