👉 In mathematics, a summation is a mathematical operation that adds up all of the terms in an expression. It can be represented by using the symbol β (sigma) or sigma notation. For example: 1. β(x + y) = x + y + ... for any set of real numbers {x, y} 2. β(n^2 - 3n + 2) = n^2 - 3n + 2 for all integers n