lean_workbook_plus_71847

Proved

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

Given that $a>0$ and $b>0$ prove that $\sqrt{ab}\ge\frac{2ab}{a+b}$ .

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_71847 (a b : ℝ) (ha : 0 < a) (hb : 0 < b) : Real.sqrt (a * b) ≥ 2 * a * b / (a + b)   :=  by sorry

Source