lean_workbook_plus_40840

Proved

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

Let $x$ be a real number with $x \ge 1$ . Prove that $x^3 - 5x^2 + 8x - 4 \ge 0$ .

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_40840 (x : ℝ) (h : x ≥ 1) : x^3 - 5 * x^2 + 8 * x - 4 ≥ 0   :=  by sorry

Source