Online tool to check if number is rational or irrational? I am new to this forum. I've been programing for some time, and now starting my engineering degree. I am trying to find an online utility that will help me grasp the concept of irrational numbers (summary, multiplication, devision etc.) through trial and error. I am looking for an online tool that will give me a yes no answer if a number is rational or irratioonall. 
Do you know of any such tools? 
I Hope this question is in the right stackexchange site.

You can simply try Wolfram|Alpha.
