Homework Statement
I have a particle moving with uniform velocity in a frame ##S##, with coordinates $$ x^\mu , \mu=0,1,2,3. $$
I need to show that the particle also has uniform velocity in a frame ## S' ##, given by
$$x'^\mu=\dfrac{A_\nu^\mu x^\nu + b^\mu}{c_\nu x^\nu + d}, $$
with ##...