lean_workbook_plus_12721
ProvedProve that .
Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_12721 (x y z : ℝ) :
(x - y) ^ 4 + (y - z) ^ 4 + (z - x) ^ 4 =
2 * (x ^ 2 + y ^ 2 + z ^ 2 - x * y - y * z - z * x) ^ 2 := by sorrySource