lean_workbook_plus_25992

Proved

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

Let $a,b$ be positive real numbers such that $a+b=1$ . Prove that $ab^2\le\frac{4}{27}$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_25992 (a b : ℝ) (ha : 0 < a) (hb : 0 < b) (hab : a + b = 1) : a * b^2 ≤ 4/27   :=  by sorry

Source