Metamath Proof Explorer


Theorem sdrginvcl

Description: A sub-division-ring is closed under the ring inverse operation. (Contributed by Thierry Arnoux, 15-Jan-2025)

Ref Expression
Hypotheses sdrginvcl.i
|- I = ( invr ` R )
sdrginvcl.0
|- .0. = ( 0g ` R )
Assertion sdrginvcl
|- ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> ( I ` X ) e. A )

Proof

Step Hyp Ref Expression
1 sdrginvcl.i
 |-  I = ( invr ` R )
2 sdrginvcl.0
 |-  .0. = ( 0g ` R )
3 issdrg
 |-  ( A e. ( SubDRing ` R ) <-> ( R e. DivRing /\ A e. ( SubRing ` R ) /\ ( R |`s A ) e. DivRing ) )
4 3 biimpi
 |-  ( A e. ( SubDRing ` R ) -> ( R e. DivRing /\ A e. ( SubRing ` R ) /\ ( R |`s A ) e. DivRing ) )
5 4 3ad2ant1
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> ( R e. DivRing /\ A e. ( SubRing ` R ) /\ ( R |`s A ) e. DivRing ) )
6 5 simp3d
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> ( R |`s A ) e. DivRing )
7 simp2
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> X e. A )
8 5 simp2d
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> A e. ( SubRing ` R ) )
9 eqid
 |-  ( R |`s A ) = ( R |`s A )
10 9 subrgbas
 |-  ( A e. ( SubRing ` R ) -> A = ( Base ` ( R |`s A ) ) )
11 8 10 syl
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> A = ( Base ` ( R |`s A ) ) )
12 7 11 eleqtrd
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> X e. ( Base ` ( R |`s A ) ) )
13 simp3
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> X =/= .0. )
14 9 2 subrg0
 |-  ( A e. ( SubRing ` R ) -> .0. = ( 0g ` ( R |`s A ) ) )
15 8 14 syl
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> .0. = ( 0g ` ( R |`s A ) ) )
16 13 15 neeqtrd
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> X =/= ( 0g ` ( R |`s A ) ) )
17 eqid
 |-  ( Base ` ( R |`s A ) ) = ( Base ` ( R |`s A ) )
18 eqid
 |-  ( 0g ` ( R |`s A ) ) = ( 0g ` ( R |`s A ) )
19 eqid
 |-  ( invr ` ( R |`s A ) ) = ( invr ` ( R |`s A ) )
20 17 18 19 drnginvrcl
 |-  ( ( ( R |`s A ) e. DivRing /\ X e. ( Base ` ( R |`s A ) ) /\ X =/= ( 0g ` ( R |`s A ) ) ) -> ( ( invr ` ( R |`s A ) ) ` X ) e. ( Base ` ( R |`s A ) ) )
21 6 12 16 20 syl3anc
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> ( ( invr ` ( R |`s A ) ) ` X ) e. ( Base ` ( R |`s A ) ) )
22 eqid
 |-  ( Unit ` ( R |`s A ) ) = ( Unit ` ( R |`s A ) )
23 17 22 18 drngunit
 |-  ( ( R |`s A ) e. DivRing -> ( X e. ( Unit ` ( R |`s A ) ) <-> ( X e. ( Base ` ( R |`s A ) ) /\ X =/= ( 0g ` ( R |`s A ) ) ) ) )
24 23 biimpar
 |-  ( ( ( R |`s A ) e. DivRing /\ ( X e. ( Base ` ( R |`s A ) ) /\ X =/= ( 0g ` ( R |`s A ) ) ) ) -> X e. ( Unit ` ( R |`s A ) ) )
25 6 12 16 24 syl12anc
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> X e. ( Unit ` ( R |`s A ) ) )
26 9 1 22 19 subrginv
 |-  ( ( A e. ( SubRing ` R ) /\ X e. ( Unit ` ( R |`s A ) ) ) -> ( I ` X ) = ( ( invr ` ( R |`s A ) ) ` X ) )
27 8 25 26 syl2anc
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> ( I ` X ) = ( ( invr ` ( R |`s A ) ) ` X ) )
28 21 27 11 3eltr4d
 |-  ( ( A e. ( SubDRing ` R ) /\ X e. A /\ X =/= .0. ) -> ( I ` X ) e. A )