lean_workbook_plus_37983

Proved

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

By CS: \n $\sum\frac{a+2c}{a+b}=\sum\frac{(a+2c)^2}{(a+2c)(a+b)}\ge \frac{9\sum a^2+18\sum ab}{\sum a^2+5\sum ab}\ge \frac{9}{2}$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_37983 {a b c : ℝ} (ha : 0 < a) (hb : 0 < b) (hc : 0 < c) : (a + 2 * c) / (a + b) + (b + 2 * a) / (b + c) + (c + 2 * b) / (c + a) ≥ 9 / 2   :=  by sorry

Source

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

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