lean_workbook_plus_17171
ProvedIt is given to make use of the identity- \n
Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_17171 (a b c x y z : ℝ) : (a * x + b * y + c * z) ^ 2 + (a * y - b * x) ^ 2 + (b * z - c * y) ^ 2 + (c * x - a * z) ^ 2 = (a ^ 2 + b ^ 2 + c ^ 2) * (x ^ 2 + y ^ 2 + z ^ 2) := by sorry
Source