- #1
mertcan
- 345
- 6
Hi, I would like to express that r and r' are vectors in the attachment and let's say that r is observer distance vector r' is source distance vector. By the way I know this is taylor expansion (for instance if there was only x component (scalar form) I would not any ask question ). But I do not understand when we include vectors, why there is a dot product of r and r'?? Also I know the taylor expansion of multiple scalar variables but I do not know how to derive taylor expansion of multiple vector variables ( I think 1/distance is a scalar function comprised of 2 different vectors here )?