I'm just having a bit of trouble remembering the process of some of the integral rules, namely the power rule and the 'indefinite integral of a constant multiple of a function.

Basically, the example in my textbook is as follows (Not sure how to do the integral symbol, so hope this all make sense - I'll use 'int.' to denote that symbol).

(No issues understanding this)

(Again, no issues here)

This is where I get a little lost. I have no idea where the 2 comes from in this part. I would have thought that from

it would in fact be

, which would just be x^(-1/2).

Obviously, I'm going wrong here, so an explanation would be great. The textbook makes no mention of why this occurs and it's most likely something simple..

Cheers