# Hard Integral Question

Tags:
1. Jan 13, 2016

### Utilite

Please help, I am not sure if you can read my latex code. A friend of mine sent this to me before her final exam, I have been trying to solve it for 3-4 days. I used some substitutions, I tried integration by parts but couldn't get a solution. I used wolfram alpha but it needs more time and for that I have to be premium. I couldn't get this solved on Matlab.
$\int_{0}^{\infty}\frac{x}{x^2+1}\tan{x}\cos{((\tan(x))^2)}dx$

2. Jan 13, 2016

### axmls

Where does this integral come from? It doesn't appear to have an elementary antiderivative, so do you have any reason to believe you'll be able to find a closed-form solution?

3. Jan 13, 2016

### Utilite

Well, I just asked my friend she said that she didn't actually take this from a textbook. There was a book or something a guy is talking about his high school life and then there is this integral on the page like an image or something. Well, it turns out I was just wasting my time.
Still, I wonder do you have solution of this, the one thing comes to my mind is to find Taylor series of each function and integrate.