Hi,
I wasn't sure where to post this, hope it's right.
Anyway, what is the meaning of this
$\displaystyle \Sigma_{k=1}^n \frac{kČ}{2^k}=6-\frac{nČ+4n+6}{2^n}$
i know it's some kind of sum, but a sum of what?
It's a summation.
Summation - Wikipedia, the free encyclopedia