no goals
R : Type u
S : Type u_1
inst✝¹ : Ring R
inst✝ : Semiring S
f : R →+* S
x : S
p : R[X]
⊢ eval₂ f x p = eval₂ (RingHom.comp f (Subring.subtype (Subring.closure ↑(frange p)))) x (restriction p)
simp only [eval₂_eq_sum, sum, support_restriction, ← @coeff_restriction _ _ p, RingHom.comp_apply,
  Subring.coeSubtype]