Calculus

You dont need infinities and calculus to do 3D graphics and video games.

Here is why:
http://www.youtube.com/watch?v=Oe2DZc6BXZk

that is, all the trigonometry you learned at school was a waste of your time, as it could be replaced with linear algebra.

sine can be finitely approximated and therefore requires no belief in infinitesmal quantities - you would know that if you actually went to college instead of basement dwelling