lean_workbook_plus_55720

Proved

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

Let $x,y>0$ and $\frac{1}{x + 2} + \frac{2}{y + 2} = \frac{1}{3}.$ Prove that

x+2y\geq 21

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_55720 (x y : ℝ) (hx : 0 < x) (hy : 0 < y) (h : 1 / (x + 2) + 2 / (y + 2) = 1 / 3) : x + 2 * y ≥ 21   :=  by sorry

Source