English
Multiplying a polynomial by X corresponds to multiplying its evaluation by x.
Русский
Умножение полинома на X соответствует умножению его оценки на x.
LaTeX
$$$\operatorname{ev}_{f,x}(p \cdot X) = \operatorname{ev}_{f,x}(p) \cdot x$$$
Lean4
theorem eval₂_mul_C' (h : Commute (f a) x) : eval₂ f x (p * C a) = eval₂ f x p * f a :=
by
rw [eval₂_mul_noncomm, eval₂_C]
intro k
by_cases hk : k = 0
· simp only [hk, h, coeff_C_zero]
· simp only [coeff_C_ne_zero hk, RingHom.map_zero, Commute.zero_left]