r = -rac(5 - \sqrt5)(\sqrt5 + 1)(\sqrt5 - 1)(\sqrt5 + 1) = -rac5\sqrt5 + 5 - 5 - \sqrt55 - 1 = -rac4\sqrt54 = -\sqrt5. - AMAZONAWS

📅 March 6, 2026 👤 scraface

Mar 06, 2026

$r = - rac{(5 - \sqrt{5})(\sqrt{5} + 1)}{(\sqrt{5} - 1)(\sqrt{5} + 1)} = - rac{5\sqrt{5} + 5 - 5 - \sqrt{5}}{5 - 1} = - rac{4\sqrt{5}}{4} = -\sqrt{5}.$