lean_workbook_plus_18134

Proved

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

Let $a, b, c$ be real numbers such that $a^2+ab+b^2=3.$ Prove that

(a^2-a+1)(b^2-b+1)\geq 1

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_18134 (a b c : ℝ) (hab : a^2 + a * b + b^2 = 3) : (a^2 - a + 1) * (b^2 - b + 1) ≥ 1   :=  by sorry

Source