Integral fraction equation I'm learning calculus and I'm trying to do the below integral (with working). 
$$\int {\sqrt x \over x^2}dx$$
So I start by making $u=\sqrt x$ and $x^2=u \cdot u^3$
$$\int {\sqrt u \over u \cdot u^3}dx$$
So I'm a bit lost with the next step. What do I do with $dx$?

Hint
If you do not want to work with fractional exponents :
$$I=\int {\sqrt x \over x^2}dx$$ Change variable $u=\sqrt x$, $x=u^2$, $dx=2u \,du$. All of that makes $$I=\int \frac{u}{u^4}2u\,du$$ I am sure that you can take from here.
