You can use the digits 1,2,and 3 once only and any mathematical symbols you are aware of, but no symbol is to be used more than once. The challenge is to see if you can make the smallest positive number.
Special rules: You cannot use Euler's number or pi or infinity.
Special thanks to: Rhonda Wendel for Make the most of these digits and for the problem text which was slightly altered.
Using a trig identity, I can get an incredibly small number from the very large number (.1^-2e3)! [The solution to Make The Most Of These Digits.]
cot tan x = 1/x, so: cot tan [(.1^-2e3)!] is my very small number