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I recently had a problem. I know how to evaluate power series but I cannot seem to find an expansion for $\sqrt{x+1}$.

I've tried differentiating it, in order to bring it in reciprocal form but that didn't help. Due to the presence of square root, I cannot change it in the form of $1/(x+1)$.

Kindly help.

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    http://en.wikipedia.org/wiki/Binomial_series2012-08-04
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    Please excuse my ignorance. Is binomial series the same as power series?2012-08-04
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    The binomial series is one of the power series that you should be very familiar with.2012-08-04
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    I am, I know how to calculate the binomial series. Just a bit rusty with the concepts. So binomial series is a kind of power series. Thank you for the comment! :)2012-08-04
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    Just to check: you know how to interpret things like $\binom{1/2}{k}$, yes?2012-08-04
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    Yes, this is the combination form. (1/2)!/((k!)(1/2-k)!).2012-08-04
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    No sorry, whats the deal with (1/2)! How to evaluate that?2012-08-04
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    Use the [Gamma function](http://en.wikipedia.org/wiki/Gamma_function) $\Gamma(x+1)=x!$ and generalises for $x\in R$.2012-08-04
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    No need to call on the Gamma function. $${1/2\choose k}={(1/2)(-1/2)\cdots((3/2)-k)\over k!}$$2012-08-04
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    In fact, $$\binom{1/2}{k}=\frac1{1-2k}\binom{2k}{k}\left(-\frac14\right)^k$$2012-08-04
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    Okay thank you guys for enlightening me, but you know what? This got me kinda confused, this is something I haven't studied. I'm willing to delve into this topic if only I had an idea where to start. Thank you once again.2012-08-04

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