1. The problem statement, all variables and given/known data With constant acceleration prove that the average velocity from t1 to t2 =t1 + Δt is equal to the instanous velocity in the middle of the time interval between t1 and t2. 2. Relevant equations What I am looking for is a general equation that does not involve accelaration. All I have is position. By the way this is 1-D kinematics so no need for vectors. 3. The attempt at a solution Tried all sorts of subs with Vavg= (Vi + Vf)/2 and Vavg= Δx/Δt I tried subbing these in to many of the other equations such as Vf=Vi+at. I imagine there is some sort of trick to it. This thing is driving me nuts.