$\displaystyle \int{\frac{x^2}{x^2+1}}$

I set up a substitution and made $\displaystyle u=x^2+1$ so I could rewrite the integral as $\displaystyle \frac{u-1}{u}$ but my TI-89 is giving me the answer as $\displaystyle x-\arctan{x}$

I was thinking of using a trig-substitution, but this is for a friend of mine's homework, and he hasn't learned those yet. I know it's something simple that I'm missing, but I can't figure it out.