Understanding the Binomial Expansion and its Relationship to e^p

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thereddevils
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How is

[tex]1+p+\frac{p^2}{2!}+\frac{p^3}{3!}+...=e^p[/tex] ?
 
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I know it has to do with taylor expansions, but I've never studied this so I can't answer your question. I'd also like to see a proof for this so this is like some pointless post I'm making so I can subscribe to this thread :biggrin:
 
Depends how you define e^p. You could just define it as the power series. However, I'm assuming you are using something like...

[tex] e^p = \lim_{n \rightarrow \infty} (1 + \frac{p}{n})^n[/tex]

Try using the binomial theorem on the right side, then take the limit.
 
thereddevils said:
How is

[tex]1+p+\frac{p^2}{2!}+\frac{p^3}{3!}+...=e^p[/tex] ?

Mentallic said:
I know it has to do with taylor expansions, but I've never studied this so I can't answer your question. I'd also like to see a proof for this so this is like some pointless post I'm making so I can subscribe to this thread :biggrin:

You just show the remainder upon approximating it with the first n terms goes to zero as n --> infinity. See, for example,

http://en.wikipedia.org/wiki/Taylor's_theorem