lean_workbook_plus_51982

Proved

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

Prove that $\frac{a^2}{a^2+4}+\frac{2}{1+(a+1)^2} \geq \frac{3}{5}$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_51982 (a : ℝ) : (a^2/(a^2 + 4) + 2/(1 + (a + 1)^2)) ≥ 3/5   :=  by sorry

Source