lean_workbook_plus_17577Openby Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)观察到x2+6=(xcosx−3sinx)(xcosx−2sinx)−(xsinx+3cosx)(−xsinx−2cosx)x^2+6=(x\cos{x}-3\sin{x})(x\cos{x}-2\sin{x})-(x\sin{x}+3\cos{x})(-x\sin{x}-2\cos{x})x2+6=(xcosx−3sinx)(xcosx−2sinx)−(xsinx+3cosx)(−xsinx−2cosx)Preambleimport Mathlib.Analysis.Complex.BasicFormal statementtheorem lean_workbook_plus_17577 : ∀ x : ℝ, x^2 + 6 = (x * cos x - 3 * sin x) * (x * cos x - 2 * sin x) - (x * sin x + 3 * cos x) * (-x * sin x - 2 * cos x) := by sorrySourcehttps://huggingface.co/datasets/internlm/Lean-WorkbookView graph