So if I have an equation x'=(x(cross)n)+a
where x is the position vector, x' time derivative, n unit constant, a constant, then I get changing by x->x+c:
(x+c)'=((x+c)(cross)(n+c))+(a+c)
is this what you meant?
In a general situation, how do you change origin (mathematically speaking) in a physical context i.e. with position vectors, constant vectors, unit vectors to certain directions ... ?
I am a bit confused with the concept.