Question

How do you integrate sqrt(arctanx)?

Answer 1

Wolfram alpha is your friend.

Answer 2

And if that doesn't help, google is too.

Answer 3

http://www.wolframalpha.com/input/?i=integrate+sqrt%28arctan%28x%29%29+dx

so basically you can't integrate it, but if you have limits you can approximate the definate integral using numerical methods