Determine divergence or convergence

[spacewater]

Using Integral Test

?
? arctan n / n^2 + 1
n=1

? tan^-1 / x^2 + 1 dx

Can someone who isnt too busy explain to me where to go after this ? Thank you

 

[galactus]

\(\displaystyle \int\frac{tan^{-1}(x)}{x^{2}+1}dx\)

Let \(\displaystyle u=tan^{-1}(x), \;\ du=\frac{1}{1+x^{2}}dx\)