1. The problem statement, all variables and given/known data I keep getting it wrong. Using the quotient rule. 2. Relevant equations Derivative of (50t)/(6+t)^3 3. The attempt at a solution My answer: -100t^3 - 900t^2 + 10800/((6+t)^3)^2) The book: (-100 (t - 3))/(6 + t)^4 What happened? EDIT: Nevermind, I realize they're basically the same. I'll leave this here incase someone needs help in the future.