Well I don't see it but I've done a similar integral once and the answer was 0 due to that the integrated function was odd and the bounds of the integral were opposed in signs. I'd like to "see" what you see... so if it's not too much asked, message me in private so others can do your integral.
also Mathstud28 don't bump your thread constantly, its actually against the site rules.
"I just wanted it known that erf(x) is odd". You succeed with me... Since I almost never studied this function I didn't know that it was odd. Anyway, I believe that it wasn't that easy to see that the integral was equal to 0... If you have never done a similar exercise, then it's quite hard.