lean_workbook_plus_14644

Proved

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

Let $a,b,c$ be real numbers such that $a+b+c=1$ and $a^3+b^3+c^3=25$ . Find the value of $(a-1)(b-1)(c-1)$ .

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_14644 (a b c : ℝ) (h₁ : a + b + c = 1) (h₂ : a^3 + b^3 + c^3 = 25) : (a - 1) * (b - 1) * (c - 1) = 8   :=  by sorry

Source