Keeping track of constants in messy integrations I'm currently working through the textbook "Introduction to Electrodynamics" by David Griffiths, and there are some challenging problems in the chapter on electrostatics that involve (relatively, at least for me) long integrals in spherical and cylindrical coordinates.  It takes me a couple of pages to work through them, and I'm finding that unfortunately I'm making a lot of careless mistakes because I'm having trouble keeping track of all the constants that pile up outside the integration as I go along.  I've attempted to simplify everything "on the fly" as I do in simpler problems but it hasn't worked out very well - does anyone have any systematic methods they use in situations like this to avoid careless errors?
edit: I didn't word the question very well, the "constants" I'm speaking of are the type that end up in front of the integration, from U substitutions and such.

If all your constants are actually outside the integration, just write "$A = $ my constants" for all of them somewhere on a box in your paper and refer back to it when necessary. Then at each integration step you only need to write $A$ on the outside.
