case intro.intro.intro.intro.intro.intro.intro.intro
q : ℤ[X]
k m n : ℕ
hkm : k < m
hmn : m < n
u v w : ℤˣ
⊢ card (support (trinomial k m n ↑u ↑v ↑w)) = 3
p q : ℤ[X]
hp : IsUnitTrinomial p
⊢ card (support p) = 3
obtain ⟨k, m, n, hkm, hmn, u, v, w, rfl⟩ := hp
no goals
case intro.intro.intro.intro.intro.intro.intro.intro
q : ℤ[X]
k m n : ℕ
hkm : k < m
hmn : m < n
u v w : ℤˣ
⊢ card (support (trinomial k m n ↑u ↑v ↑w)) = 3
exact card_support_trinomial hkm hmn u.ne_zero v.ne_zero w.ne_zero