Metamath Proof Explorer


Theorem fldextsubrg

Description: Field extension implies a subring relation. (Contributed by Thierry Arnoux, 29-Jul-2023)

Ref Expression
Hypothesis fldextsubrg.1 U=BaseF
Assertion fldextsubrg E/FldExtFUSubRingE

Proof

Step Hyp Ref Expression
1 fldextsubrg.1 U=BaseF
2 fldextfld1 E/FldExtFEField
3 fldextfld2 E/FldExtFFField
4 brfldext EFieldFFieldE/FldExtFF=E𝑠BaseFBaseFSubRingE
5 2 3 4 syl2anc E/FldExtFE/FldExtFF=E𝑠BaseFBaseFSubRingE
6 5 ibi E/FldExtFF=E𝑠BaseFBaseFSubRingE
7 6 simprd E/FldExtFBaseFSubRingE
8 1 7 eqeltrid E/FldExtFUSubRingE