For a real number $\alpha > 0 $ call $\displaystyle \binom{\alpha}{n}:=\frac{\alpha(\alpha-1)(\alpha-2)...(\alpha+1-n)}{n!}$ the generalized binomial coeeficient. The products in the denominator and the numerator have $n$ factors for each. Assume that $\alpha \notin \mathbb{N}$.\\\\ a) Prove: $\lim_{n \to \infty}\frac{\binom{\alpha}{n+1}}{\binom{\alpha}{n}} = 1$
\[\displaystyle \binom{\alpha}{n}:=\frac{\alpha(\alpha-1)(\alpha-2)...(\alpha+1-n)}{n!}\] Prove: \[\Large \lim_{n \to \infty}\frac{\binom{\alpha}{n+1}}{\binom{\alpha}{n}} = 1\]
\[\Large {{\alpha \choose n+1} \over {\alpha \choose n}}={a-n \over n+1}\]
ls It answer?
I just simplified it.... you still need to take the limit: \[\Large \lim_{n \to \infty}{\alpha-n \over n+1}\]
i don't know how it is =1 :'(
thanks your effort tomorrow i must give very important homework i think i need a longer solution so that my mentor give me enough points :( and i have no idea how to start..
\[(α(α−1)(α−2)...(α−n+1)(α−n)/(n+1)!)/(α(α−1)(α−2)...(α−n+1)/n!)\] \[=(α−n)/(n+1)!)/1/n!=(α−n)n!/(n+1)!=(α−n)/(n+1)=α/(n+1)-n/(n+1)\] When n goes to infinity, α/(n+1) goes to 0, and -n/(n+1) goes to -1. So I get -1. Let me try to do it again....
ok it sounds hopefully
I'm honestly not seeing how it could be something other than -1. If you take some number \(\alpha\) and fix it in \(\mathbb{R}^+ \setminus \mathbb{N}\), Then as \(n\) goes to infinity, there comes a point where\[\binom{\alpha}{n}>0\]\[\binom{\alpha}{n+1}<0\]Because of the \(\alpha\cdot(\alpha-1)\cdot...\cdot(\alpha-(n-1))\) terms.This means that the numerator and denominator of \[\Large {{\alpha \choose n+1} \over {\alpha \choose n}}\]will have differing signs when \(\alpha-n<0\) and \(\alpha-n+1>0\). Hence, as \(n\) goes to infinity, it must be negative. And from what nightwill just showed above, it should be exactly \(-1\).
I was a little unclear at the end. They will have differing signs because if \(\alpha\cdot(\alpha-1)\cdot...\cdot(\alpha-(n+1))\) has an odd number of negative numbers, then \(\alpha\cdot(\alpha-1)\cdot...\cdot(\alpha-n)\) must have an even number of negative numbers and vice versa as \(\displaystyle n\rightarrow \infty\)
Also KongGeorge are you agreed with the solution of Nightwill?
I'm agreeing with nightwill
ok thank you very much for your efforts
Also, @PaxPolaris take a look at http://www.wolframalpha.com/input/?i=6.5+choose+9 The property you listed only seems to hold when \(\alpha\) is a natural number.
right sorry...
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