lean_workbook_plus_11395

Proved

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

prove that: $\frac{1}{a} + \frac{1}{b} + \frac{1}{c} \ge \frac{9}{{a + b + c}}$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_11395 {a b c : ℝ} (ha : a > 0) (hb : b > 0) (hc : c > 0) : 1 / a + 1 / b + 1 / c ≥ 9 / (a + b + c)   :=  by sorry

Source