English
Same as previous: aeval (C x) p = mapAlgHom (aeval x) (swap p).
Русский
То же самое: aeval(C x) p = mapAlgHom(aeval x)(swap p).
LaTeX
$$$\\mathrm{aeval}(\\mathrm{C}\\;x)\\; p = \\mathrm{mapAlgHom}(\\mathrm{aeval}(x))\\Bigl(\\mathrm{swap}(p)\\Bigr).$$$
Lean4
/-- If the evaluation (`evalEval`) of a bivariate polynomial `p : R[X][Y]` at a point (x,y)
is zero, then `Polynomial.evalEval x y` factors through `AdjoinRoot.evalEval`, a ring homomorphism
from `AdjoinRoot p` to `R`. -/
@[simps!]
noncomputable def evalEval : AdjoinRoot p →+* R :=
lift (evalRingHom x) y <| eval₂_evalRingHom x ▸ h