lean_workbook_plus_72012

Proved

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

Let $a>b>0$ and $a^5 + b^5 =a-b.$ Prove that

a^4 +2b^4 <1.

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_72012 {a b : ℝ} (h1 : a > b) (h2 : b > 0) (h3 : a^5 + b^5 = a - b) : a^4 + 2 * b^4 < 1   :=  by sorry

Source