Despite any desire to be perfect, it's a permanent impossibility you must live with and strive to remove despite it being as permanent as the existence of matter in the universe.
You're very lucky you can even do calculus, I got confused and turned around in Geometry...
The only perfection in the world is the natural perfection of the continuation of life despite the rigors and trials facing them.
There's no dishonor in mistakes, there's only room for improvement. One should always strive to be the best they can, and when they face a challenge or obstacle, it's just another thing to overcome.
In short, don't worry too much about it, just answer it right next time.
You do have the guts to say that. If this was the salty spitoon, Neo would have taken you in.
[Edited by HonestGamer, 9/4/2010 12:24:00 AM]