First I'd like to say that I'm getting back into college after several years out in the job market. Unfortunately, I need to complete several more upper division math courses before I can complete my CS degree. Before I go back and start taking my classes again, I've been trying to self-study my way back through Calc I, and having difficulty just getting beyond the first section. Maybe I just need to refamiliarize myself with the basics. What has me stuck is determining the distance between two points. Pretty simple. I understand the theory, and can work the problems well, until I got to this one, and I've been stuck. Determine the distance between two points: (1,√3), (-1,1) My book shows the answer as: √(8-2√3) (I'm at work, I'll need to verify this, but 99% sure this is what the book states. I do know the question is 100% correct.) When I apply the distance formula: √((X2-X1)^2+(Y2-Y1)^2) I get: √((-1-1)^2+(1-√3)^2) When I reduce this I get: √(4+(1-√3)^2) Am I not reducing this far enough? If so, how do you reduce down to √(8-2√3)? Thanks for your help and patience!