**Re: Integral Question When Evaluating Expected Value of Order Statistics**

Hello Dragan,

Many thanks for your help.

The answer in my first post is from an article which I searched and downloaded from Internet, it seems the article is part of a book. So, there is no author information. If you need the said article (PDF format), I can email to you

I double confirmed and verified that the answer is correct.

Today, I use the advice that you gave me when you first replied to my post, that is, fold the pdf and cdf. The attached is my detailed devrivation. but the final result is still different from the answer in my first post, which is correct, I have double confirmed and verified.

So, up to now, there are three answers to the same question, the first one is from an article from an unknown author, the second is from your above reply, the third is my today's derivation, which I used the idea that you told me : fold the pdf and cdf.

If the answer from the said unknown author is correct ( I am sure it is correct), where is our mistake in the derivation ? I double checked my today's devrivation, I didn't find out any mistake, please see the attached.

Your reply and help is highly appreciated!

Other order statistic experts are more than welcomed to help with this question!