Recent content by MrKushtrim

## \frac{1}{(1 -q)^r } ## But how would I prove that ? --- Edit: I checked a wikipedia article about binomial series, and it turns out that the series \sum_{m=0}^\infty \frac{(m + r - 1)!}{(r-1)!m!}q^m is of this form , where ##β= r-1## and ##z=q## Thanks for the help :) Though, is...

Hi, thanks for the reply . It must equal 1. Though I have no idea how to prove it. Thanks, I had the terminology mixed up. To be a probability mass function , ##f_k## has to be positive, and the sum over all ## k ## has to be 1. It's easy to see that ##f_k## is positive, but I cannot seem...

Hi, Could someone help me prove that the function given with ##f(x) = \binom{x-1}{r-1} p^{r}(1-p)^{x-r}## is a probability density function, where ## x= r, r+1,..., \infty ## and ## 0<p<1 ## I thought to solve it somehow by using the binomial theorem, but since it's the upper part...