by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)
prove that \n\n (x+y+z)(−2(x+y+z)xyz+(xy+zx+yz)2)−2(xy+zx+yz)xyz≥x2z3+x3y2+y3z2\n\nx,y,z>0
Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_27794 (x y z : ℝ) (hx : 0 < x) (hy : 0 < y) (hz : 0 < z) : (x + y + z) * (-(2 * (x + y + z) * x * y * z) + (x * y + y * z + z * x) ^ 2) - 2 * (x * y + y * z + z * x) * x * y * z ≥ x ^ 2 * z ^ 3 + x ^ 3 * y ^ 2 + y ^ 3 * z ^ 2 := by sorry