1. The problem statement, all variables and given/known data 2 INERTIAL frames S and S': Coordinates of S: (x,y,z,t) Coordinates of S': (x',y',z',t') Whereby: x': x-ut y': y z': z t': t The point is how do you convert the coordinates of S' to the ones in Lorentz transformation. I know the formulas but I do not know how to derive them. I'm new to this concept. No complicated things.. :P I know the meaning of Lorentz factor... so yeah.