1. The problem statement, all variables and given/known data I have two x,y,z coordinates - a & b. I know the distance between the coordinates. I need to get a 3D vector which represent the direction between vector a and vector b. 2. Relevant equations I am unsure as to whether the I should simply substract each respective coordinate value from one to the other i.e. (x1-x2,y1-y2,z1-z2) 3. The attempt at a solution I tried to apply the forumula above to a trivial case e.g. A = (1,1,1); B = (2,2,2); C=(2-1,2-1,2-1,)=(1,1,1) I am not sure if this is right.