lean_workbook_plus_71047

Proved

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

If $a,b>0$ and $a(a+b)^2=4$ , then prove: $a^3b(a^2+b^2){\leq}2$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_71047 (a b : ℝ) (ha : 0 < a) (hb : 0 < b) (hab : a * (a + b) ^ 2 = 4) : a ^ 3 * b * (a ^ 2 + b ^ 2) ≤ 2   :=  by sorry

Source