theorem extracted_formal_statement_55 {n m : ℕ+} {b : Fin ↑m → ℝ} {A : Matrix (Fin ↑m) (Fin ↑n) ℝ}
  (x : EuclideanSpace ℝ (Fin ↑n)) : Aᵀ *ᵥ A *ᵥ x = (1 / 2) • 2 • Aᵀ *ᵥ A *ᵥ x := sorry

State before:
n m : ℕ+
b : Fin ↑m → ℝ
A : Matrix (Fin ↑m) (Fin ↑n) ℝ
x✝ : EuclideanSpace ℝ (Fin ↑n)
f : EuclideanSpace ℝ (Fin ↑n) → ℝ := fun x => 1 / 2 * A *ᵥ x ⬝ᵥ A *ᵥ x
f' : EuclideanSpace ℝ (Fin ↑n) → Fin ↑n → ℝ := fun x => Aᵀ *ᵥ A *ᵥ x
g : EuclideanSpace ℝ (Fin ↑n) → Fin ↑n → ℝ := fun x => (1 / 2) • 2 • Aᵀ *ᵥ A *ᵥ x
x : EuclideanSpace ℝ (Fin ↑n)
⊢ Aᵀ *ᵥ A *ᵥ x = (1 / 2) • 2 • Aᵀ *ᵥ A *ᵥ x

Tactic: simp

State after:

Relevant lemmas: