Finding Components of a Vector in a 3D Space

[matteo86bo]

This might be a very stupid question but I can't come up with an answer, I hope you might help. So, I have two vector in a 3D space $\vec x$ and $\vec x^\prime$. I know that a certain quantity $\vec a$ is defined along the radial direction between the first vector with respect to the second. What are the x-,y- and z-component of the vector $\vec a$?

 

[lanedance]

i think you need to describe the question more, in particular what is "defined along the radial direction between the first vector with respect to the second"

Is this a mechanics/dynamics question?

It often helps to write exactly how it is written