Metamath Proof Explorer


Theorem sdrgss

Description: A division subring is a subset of the base set. (Contributed by Thierry Arnoux, 21-Aug-2023)

Ref Expression
Hypothesis sdrgid.1
|- B = ( Base ` R )
Assertion sdrgss
|- ( S e. ( SubDRing ` R ) -> S C_ B )

Proof

Step Hyp Ref Expression
1 sdrgid.1
 |-  B = ( Base ` R )
2 issdrg
 |-  ( S e. ( SubDRing ` R ) <-> ( R e. DivRing /\ S e. ( SubRing ` R ) /\ ( R |`s S ) e. DivRing ) )
3 1 subrgss
 |-  ( S e. ( SubRing ` R ) -> S C_ B )
4 3 3ad2ant2
 |-  ( ( R e. DivRing /\ S e. ( SubRing ` R ) /\ ( R |`s S ) e. DivRing ) -> S C_ B )
5 2 4 sylbi
 |-  ( S e. ( SubDRing ` R ) -> S C_ B )