Proving the Infinite Series: (xlna)^(n-1)/n!

Kevin Huang
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Homework Statement


Given an infinite series that follows the form [(xlna)^(n-1)]/n!
n takes on integers from 0 onwards
x all real numbers
a all positive real numbers


Homework Equations


Maclaurin series expansion


The Attempt at a Solution


In which for the e^x series expansion plug in xlna into the x from e^x to obtain a^x which is the answer to the infinite summation. However, are there any other proofs besides using Maclaurin? Thanks.
 
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Note that

e^{ax} = \sum_{n=0}^{\infty} \frac {(ax)^n}{n!}

In other words the nth term of this series is (ax)^n/n!. You have a different series. The nth term of your series is (ax)^{(n-1)}/n!.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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