So i am working on a question, which is beyond my knowledge of Lorentz transformations and some help is greatly appreciated. I have a 4 velocity, u=γ(v vector,c) and its transformation properties are the standard lorentz boost. I don't quite understand how I am supposed to do this given that there will be a transformation for each component, and I don't know whether for each component given x1*=γ(x1-Vt). Is the V in the direction of the component and if so isn't it equal to x1 anyway because x1 in this case is a velocity? Obtain the lorentz transformation for each component and then deduce the velocity addition formula for v vector. You will end up with products of different γs not entirely sure why either. Any help on this would be greatly appreciated. I have already done some assuming the velocity to be only in the first component direction which i know is wrong but i have never actually been taught the general boost yet they chuck it in the questions. Thanks.