pith. machine review for the scientific record. sign in
theorem proved term proof

polyCost_mul

show as:
view Lean formalization →

No prose has been written for this declaration yet. The Lean source and graph data below render without it.

generate prose now

formal statement (Lean)

 134theorem polyCost_mul {f g : Polynomial F} (hf : f ≠ 0) (hg : g ≠ 0) :
 135    polyCost (f * g) = polyCost f + polyCost g := by

proof body

Term-mode proof.

 136  unfold polyCost
 137  rw [normalizedFactors_mul hf hg]
 138  rw [Multiset.map_add, Multiset.sum_add]
 139
 140/-! ## Cost on irreducibles and powers -/
 141
 142/-- For a monic irreducible polynomial `P`, the cost equals `J(‖P‖)`.
 143    Mathlib's `normalizedFactors` returns the multiset of monic
 144    irreducible factors. -/

used by (3)

From the project-wide theorem graph. These declarations reference this one in their body.

depends on (13)

Lean names referenced from this declaration's body.