lean_workbook_plus_50454

Proved

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

$f(0)=f(x^2-f(x))+4f(x)^2 \implies f(0)-f(x^2-f(x))=4f(x)^2$

Preamble

import Mathlib.Analysis.Complex.Basic

Formal statement

theorem lean_workbook_plus_50454 (f : ℝ → ℝ) (hf : ∀ x, f 0 = f (x^2 - f x) + 4 * (f x)^2) : ∀ x, f 0 - f (x^2 - f x) = 4 * (f x)^2   :=  by sorry

Source