apply h₁.almost_additive
case refine_2
G : Type u_1
inst✝ : AddCommGroup G
f₁ : ℤ → ℤ
bound₁ : ℕ
h₁ : AlmostAdditive f₁ bound₁
f₂ : G → ℤ
bound₂ : ℕ
h₂ : AlmostAdditive f₂ bound₂
x y : G
⊢ |f₁ (f₂ x + f₂ y) - f₁ (f₂ x) - f₁ (f₂ y)| ≤ bound₁
no goals