lean_workbook_plus_9863
Openusing the fact that . Adding the first two and substracting the third one then gives
Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_9863 (A B : Matrix (Fin 2) (Fin 2) ℝ) : 2 * A.trace * B.trace - 2 * (A * B).trace + 2 * A.det + 2 * B.det - 2 * (A + B).det = 0 := by sorry
Source