So I'm completely lost in my class on Additive Number Theory.
I've been trying to show that there exists a constant B such that
$\sum_{n \le x}\frac{\log n}{n} = \frac{1}{2}\log ^2x + B + O\left(\frac{\log x}{x}\right) $
I've honestly been working on it all night and can't come up with a good way to approach the problem!! Help!!!
The foreign O notation is really messing with me.