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Well it reduces to $\sum\limits_{i=2}^n (i)x^{n-i}=2x^{n-2}+3x^{n-3}\cdots+(n-1)x+n$I have the following summation and I'm attempting to remove the summation notation. It appears to be the sum of a geometric series but I'm having a great deal of trouble with it. X is an unknown constant.
$$\sum\limits_{i=2}^n (n - (n-i))x^{n-i}$$
I have the following summation and I'm attempting to remove the summation notation. It appears to be the sum of a geometric series but I'm having a great deal of trouble with it. X is an unknown constant.
$$\sum\limits_{i=2}^n (n - (n-i))x^{n-i}$$
Thanks.
Thank you so much. I understand a bit more now, I guess I'm still a bit confused about
$$\sum\limits_{i=2}^n \frac{i}{x^i}=2(\frac{1}{x^2}+\frac{1}{x^3}+\frac{ 1}{x^4}+\frac{1}{x^5}+...+\frac{1}{x^n})+(\frac{1}{x^3}+\frac{1}{x^4}+\frac{1}{x^5}+...+ \frac{1}{x^n})+(\frac{1}{x^4}+\frac{1}{x^5}+\frac{ 1}{x^6}+...+\frac{1}{x^n})+...+\frac{1}{x^n}$$
in terms of why only the first set of summations is multiplied by 2. Sorry, I'm very rusty on the rules of summation.