- #1
gretun
- 146
- 0
In my book, it says that the Binomial Series is
[tex]\sum_{n=0}^{\infty }\binom{n}{r} x^n[/tex]
Where [tex]\binom{n}{r} = \frac{n(n-1)...(n-r+1)}{n!}[/tex] for [tex]r\geq1[/tex] and [tex]\binom{n}{0} = 1[/tex]
Now here is where it got to be, I know that the [tex]\binom{n}{r} = \frac{n(n-1)...(n-r+1)}{n!}[/tex] were derived through the power series, but how does it explained the original statement that [tex]\sum_{n=0}^{\infty }\binom{n}{r} x^n[/tex]?
Since [tex]\binom{n}{r}[/tex] does not actually change. I mean it is still [tex]\frac{n!}{(n-r)!r!}[/tex] and so how can you put negative n into n!?
[tex]\sum_{n=0}^{\infty }\binom{n}{r} x^n[/tex]
Where [tex]\binom{n}{r} = \frac{n(n-1)...(n-r+1)}{n!}[/tex] for [tex]r\geq1[/tex] and [tex]\binom{n}{0} = 1[/tex]
Now here is where it got to be, I know that the [tex]\binom{n}{r} = \frac{n(n-1)...(n-r+1)}{n!}[/tex] were derived through the power series, but how does it explained the original statement that [tex]\sum_{n=0}^{\infty }\binom{n}{r} x^n[/tex]?
Since [tex]\binom{n}{r}[/tex] does not actually change. I mean it is still [tex]\frac{n!}{(n-r)!r!}[/tex] and so how can you put negative n into n!?