lean_workbook_plus_5855

Proved

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

Prove that $\frac{2}{x+y}+\frac{2}{y+z}+\frac{2}{x+z}\geq\frac{9}{x+y+z}$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_5855 (x y z : ℝ) : (x + y + z > 0 ∧ x > 0 ∧ y > 0 ∧ z > 0) → 2 / (x + y) + 2 / (y + z) + 2 / (x + z) ≥ 9 / (x + y + z)   :=  by sorry

Source

https://huggingface.co/datasets/internlm/Lean-Workbook

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