hello,
I am trying to get a working version of this formula with mac osx Grapher application not working very well. any suggestions?
cheers oyster,
sorry bout the pic not sure how to write code here
I don't know the program or what you are trying to do with it but the summation
$\displaystyle \sum_{n = 1}^nq_n^2x_n^2$
makes no sense. On the one hand you are treating n as a variable, on the other you are treating it as a constant.
You might try inputting the formula as
$\displaystyle \sum_{i = 1}^nq_i^2x_i^2$
or something.
-Dan