Ok so I have a very basic clarification question about vector mechanics.
It is obvious that with displacement vectors the rules of vectors and trig apply to combining them. I cannot, however, see why we should assume that force vectors, velocity vectors etc should combine in the same way. Of course I know that they do but is this something that can be proved on paper or is it just shown experimentally?
I hope I have explained myself properly and I will try to rephrase my question and provide an example if I am not being clear.
Thanks for your help!