English
For RatFunc elements, toFractionRing respects scalar multiplication: toFractionRing(c • p) = c • toFractionRing(p).
Русский
Для элементов RatFunc отображение toFractionRing сохраняет скалярное умножение: toFractionRing(c • p) = c • toFractionRing(p).
LaTeX
$$$\forall c\in R,\; \forall p\in \mathrm{RatFunc}(K),\; \operatorname{toFractionRing}(c \cdot p) = c \cdot \operatorname{toFractionRing}(p)$$$
Lean4
theorem toFractionRing_smul [SMul R (FractionRing K[X])] (c : R) (p : RatFunc K) :
toFractionRing (c • p) = c • toFractionRing p := by
cases p
rw [← ofFractionRing_smul]