Is there a way to display the formula that was used from "Insert Function"?

I downloaded an add in for excel. The file was a ".xll". I then installed the add in and am using the formulas in the add in by using the "Insert Function" tool. The functions seem to work properly and are outputting correct results but I would like to see what the actual formulas are. The Formula Bar just says "=function1(input1,input2)".

So is there any way to see the actual formula?

Thanks,
Nate