lean_workbook_plus_72512

Proved

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

Let $a,b,c$ be real numbers such that $a+b+c=12,ab+bc+ca=45.$ Then $50\leq abc\leq 54.$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_72512 (a b c : ℝ) (h1 : a + b + c = 12) (h2 : a * b + b * c + c * a = 45) : 50 ≤ a * b * c ∧ a * b * c ≤ 54   :=  by sorry

Source