English
`R[x]/(f)` is an S-algebra; the quotient carries an algebra structure over S induced by the embedding of R into AdjoinRoot f.
Русский
`R[x]/(f)` является алгеброй над S; фактор-кольцо наследует алгебраическую структуру над S через вложение R в AdjoinRoot f.
LaTeX
$$$AdjoinRoot f \\text{ is an } S\\text{-algebra}$$$
Lean4
/-- `R[x]/(f)` is `R`-algebra -/
@[stacks 09FX "second part"]
instance [CommSemiring S] [Algebra S R] : Algebra S (AdjoinRoot f) :=
Ideal.Quotient.algebra S