Question

Why Epsilon is used?

Answer 1

Use of epsilon:

1. Epsilon is a Greek alphabet that is denoted by $\epsilon$.
2. In Mathematics it is generally used to describe very small quantities or numbers greater than $0$.
3. It is just not like any other mathematical representation of the variables $x,y,a,k$.
4. Epsilon is mostly used to denote a positive radius around a point (on the horizontal axis) as opposed to delta which is used to denote another radius (on the vertical axis).

Hence, epsilon is used as a very small quantity greater than $0$.