lean_workbook_plus_38308

Proved

by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

Prove that if $x, y, z$ are reals, then $x^2(3y^2+3z^2-2yz) \geq yz(2xy+2xz-yz)$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_38308 (x y z : ℝ) : x^2 * (3 * y^2 + 3 * z^2 - 2 * y * z) ≥ y * z * (2 * x * y + 2 * x * z - y * z)   :=  by sorry

Source