lean_workbook_plus_29534

Disproved

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

Prove that $\frac{a+b}{ab+3}+\frac{b+c}{bc+3}+\frac{c+a}{ca+3} \leq \frac{3}{2}$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_29534 : ∀ a b c : ℝ, (a + b) / (a * b + 3) + (b + c) / (b * c + 3) + (c + a) / (c * a + 3) ≤ 3 / 2   :=  by sorry

Source