I feel so silly asking this question, but is (the summation is over n1 from 1 to infinity. I have no idea how to type it with the latex)(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\sum[/tex](x1^n1)/n1!*(x^(n-n1))/(n-n1)!

= lim[tex](_{n1 \rightarrow \infty})[/tex] (1 + x/n1)^n1 * lim[tex](_{n1 \rightarrow \infty})[/tex] (1 + x/(n-n1))^(n-n1)

= exp(x1)*exp(x2)

???

I know it's simple, but I'm just not sure what the rules are for products inside sums. And also, how the heck do you learn the whole latex thing? I can't for the life of me it out.

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# Simple summation question

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