# Attempt at volume integration to compute the full field equation

You don't need any rotation matrices. Just choose a new set of variables - (r, θ,φ), with the z-axis pointing along r'.
Does that imply that my possible solution is incorrect, since it can't be expressed solely in terms of r' and the a's?

And we're integrating over a 3-D field, I was thinking, when we rotate r' into alignment with the z-axis, the 3-D field rotates as well.

#### phyzguy

A better way to think of it is that you are leaving the r' vector unchanged, but using a different set of (x,y,z) variables to do the integration.

A better way to think of it is that you are leaving the r' vector unchanged, but using a different set of (x,y,z) variables to do the integration.
hmm, but that seems like a case of relative motion; the vector unchanged and the co-ordinate system rotating, or the vector rotating and the co-ordinate system unchanged. The mathematical result should be the same.

"Attempt at volume integration to compute the full field equation"

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