Hello, I am having trouble with another Calculus 2 problem:

$\displaystyle \int \frac{lnx^2}{x}dx$

Letting $\displaystyle u = lnx^2$ I get

$\displaystyle \frac{1}{2} \int u \,du$

$\displaystyle = \frac{1}{2}\left[ \frac{u^2}{2} \right] + C$

$\displaystyle = \frac{(lnx^2)^2}{4} + C$

However, the textbook gives $\displaystyle (lnx)^2 + C$. Is this somehow another form, or what am I doing wrong?