Help with math

I am not too familiar with Actionscripts math capabilities, and searching forums hasnt helped either. Im trying to program a solver for a power function regression. I have the equation, i just need to figure how to program it. I was wondering if there is a quick way to do summation notation or do i just have to program out the entire process. Also what is the notation for the naturual log. Lastly, do parantheses work to do order of operations, or does it mess up the code since there are used for beginning and ending parameters and stuff like that in actionscript.