lean_workbook_plus_65989

Proved

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

Prove that $(x^{4}+2x^{3}+3x^{2}+3x+2)\ge(x^{2}+x)^{2}+2(|x|-1)^{2}$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_65989 : ∀ x : ℝ, (x^4 + 2*x^3 + 3*x^2 + 3*x + 2) ≥ (x^2 + x)^2 + 2 * (|x| - 1)^2   :=  by sorry

Source