Electric field at corner of charged square or cube

[NotMrX]

Hello,

I was wondering if we had a square with side length a and charges q. What would be the electric field at a corner? I can work this out by breaking stuff into components but I wondered if there was an easier way using very basic linear algebra. What about a cube? In other words are there any tricks to make it easier rather than just break it into components, add them, and find the resultant?

 

[berkeman]

It's not clear from your problem statement where the charge is with respect to the square, but my guess is that there is not a simple trick available. Adding components is something you will do a lot.