lean_workbook_plus_13113

Proved

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

Let $x$ be positive real number , Prove that $(1+x)^3(1+\frac{16}{x^3})\ge 81.$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_13113 (x : ℝ) (hx : 0 < x) : (1 + x) ^ 3 * (1 + 16 / x ^ 3) ≥ 81   :=  by sorry

Source