lean_workbook_plus_77129

Proved

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

Let $a,b\geq 0$ and $a+b=4.$ Prove that:\n

a+ab \leq \frac{25}{4}

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_77129 (a b : ℝ) (ha : 0 ≤ a) (hb : 0 ≤ b) (hab: a + b = 4) : a + a * b ≤ 25 / 4   :=  by sorry

Source