1. The problem statement, all variables and given/known data At t=0 the current to a dc electric motor is reversed, resulting in an angular displacement of the motor shaft given by theta(t)=246t-20.6t^2-1.47t^3 Calculate the average angular velocity for the time period from t=0 to the time calculated when the angular velocity of the motor shaft is 0. 2. Relevant equations delta(omega)/delta(time) 3. The attempt at a solution The time the velocity of the motor shaft is 4.14. I got that from taking the derivative and solving for t=0. I'm confused as to why my answer is wrong, when I plug in 4.14 into 246-41.2t-4.41t^2 to calculate the average angular velocity I get. (2(41.2)(4.14)-4.41(4.14)^2-246)/(4.14-0) I get an answer of -59.46 rad/s. Can't seem to find where I went wrong, I did this on paper as well as on calculator to make sure I wasn't punching it in wrong and I came out with approximately the same result.