r = -rac{(5 - \sqrt5)(\sqrt5 + 1)}{(\sqrt5 - 1)(\sqrt5 + 1)} = -rac{5\sqrt5 + 5 - 5 - \sqrt5}5 - 1 = -rac{4\sqrt5}4 = -\sqrt5. - AMAZONAWS

📅 March 11, 2026 👤 scraface

Mar 11, 2026

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