Posted by KC on Saturday, September 1, 2012 at 6:47pm.
lim (x->0) x^4 cos 2/x=
=lim (x->0) x^4 * lim (x>0) cos 2/x
= 0 * lim (x>0) cos 2/x
cos (a) will always be between -1 and 1. but this is irrelevant since x^4 is 0 at x=0, and anything multiplied by 0 is 0
:P