In(128/25). 15) A rough approximation for In(5) is 1.609. Use this approximation and differentials to approximate a) 1.633 b) 1.621 c) 1.632 d) 1.585 e) 1.597 16) The function f ( x ) = Inx - x x51 Imx 2+ 5 is differentiable everywhere. What is n? 1