Using the .exp() function

Using the .exp() function

I am having trouble with the built-in .exp() function.  There is no documentation that I have found on its use. 
 
When I assign a number to a variable and then attempt to use the .exp() function, Zoho will not allow me to employ a parameter with the function, i.e.,
 
  1. MyVal = 3;
  2. MyVal.exp(2);
 
After save results in:
 
  1. MyVal = 3;
  2. MyVal.exp();
 
Moreover, the function returns an odd exponential value.  For example, the above code returns a value of
20.085536923187668

Can someone please tell me what I am doing wrong?

 
Thank you,
Zack