I'd like some feedback on my approach to solving this integral

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SUMMARY

The discussion centers on the efficiency of solving the indefinite integral of an exponential function with a logarithmic power. The user employed u-substitution and integration by parts but was advised that a more efficient method exists. Specifically, the transformation a^{lnx} = x^{lna} simplifies the integration process significantly. Additionally, the importance of including the constant of integration was emphasized.

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tomvidm
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1. I gave myself the task of solving the indefinite integral of an exponential function whose base is any real valued constant and whose power is a logarithm of the variable I am integrating over. Now my question is not how to solve it, but rather, whether or not my approach was efficient. I've just started practicing doing the u-substitutions, so my approach was centered around that, but it also involved integration by parts. Below is an image of my paper containing all the information I think is needed.

6AjLzpHl.jpg


Was my choice of technique good or could I have solved this integral in some other manner?
(Also, I removed the points 2) and 3) which comes with every thread here. I think the image speaks for itself.)
 
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There is a faster way. Note that [itex]a^{lnx}=(e^{lna})^{lnx}=(e^{lnx})^{lna}=x^{lna}[/itex], which is very easy to integrate. Your answer can be simplified by noting that [itex]e^{lnx}=x[/itex] as long as x>0, and the two answers will be identical.

Edit: This is a minor point, but never forget your constant of integration!
 
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