i = pi * d^2 - d

Author:
RV'SMath
Here I have came up with the Areas of " i " Below in Graphics 1) I create all figures from the Distribution 2) I obtain the Area " i " using Hypotenuses(w) per the " Red Boxed Equation " 3) You can obtain the same numbers for " i " , while using different values for d, sigma, mu, ...