1. The problem statement, all variables and given/known data John equation of motion is Rj(t)=(t^2+3t)i + tj. David's equation of motion is Rd(t)=5ti+t^3j. At t=1 find David's velocity with respect to john. 2. Relevant equations 3. The attempt at a solution I know if you plug in the one that will give you the position they are both at when t=1. Where do I go from there to find their velocity?