lean_workbook_plus_43259

Proved

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

Prove that $x^2+y^2+z^2\geq xy+yz+xz$ for positive reals $x, y, z$ such that $xyz=1$ .

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_43259 (x y z : ℝ) (h : x*y*z = 1) : x^2 + y^2 + z^2 ≥ x*y + y*z + x*z   :=  by sorry

Source