English
For f: R →+* S1, g: σ → S2, φ: S1 →+* S2, p ∈ MvPolynomial σ R, the map version with homs satisfies eval₂Hom φ g (map f p) = eval₂Hom (φ ∘ f) g p.
Русский
Для f: R →+* S1, g: σ → S2, φ: S1 →+* S2, p ∈ MvPolynomial σ R, верно: eval₂Hom φ g (map f p) = eval₂Hom (φ ∘ f) g p.
LaTeX
$$$\\\\mathrm{eval}_2\\\\mathrm{Hom} \\\\phi g (\\\\mathrm{map}_f p) = \\\\mathrm{eval}_2\\\\mathrm{Hom} (\\\\phi \\\\circ f) g p$$$
Lean4
@[simp]
theorem eval₂Hom_map_hom [CommSemiring S₂] (f : R →+* S₁) (g : σ → S₂) (φ : S₁ →+* S₂) (p : MvPolynomial σ R) :
eval₂Hom φ g (map f p) = eval₂Hom (φ.comp f) g p :=
eval₂_map f g φ p