lean_workbook_plus_78195

Disproved

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

Prove: $\frac{2 a (a - 1)^2 (2 a + 1)}{(a^2 + 2 a + 3) (3 a^2 + 2 a + 1)} \geq 0$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_78195 : ∀ a : ℝ, (2 * a * (a - 1) ^ 2 * (2 * a + 1)) / (a ^ 2 + 2 * a + 3) / (3 * a ^ 2 + 2 * a + 1) ≥ 0   :=  by sorry

Source