The symbol Σ (capital sigma) is often used as shorthand notation to indicate the sum of a number of similar terms. Sigma notation is used extensively in statistics.

Sigma notation is a mathematical shorthand for expressing sums where every term is of the same form. For example, suppose we want to write out the sum of all the integers from 1 to 100, inclusively.

Because sigma notation is just a new way of writing addition, the usual properties of addition still apply, but a couple of the important ones look a little different.

To write a sum in sigma notation, try to find a formula involving a variable k where the first term can be obtained by setting k = 1, the second term by k = 2, and so on.

10 1 + 4 + 9 + · · · + 100 = 12+ 22+ 32+ · · · + 102 = X i2 . i=1 Given the sum of the first five odd numbers 1 + 3 + 5 + 7 + 9, we can write this in sigma notation by considering the terms as qi = 2i−1: …

Sigma notation is used to express many additions at once. Understanding what this notation is, how it works, and how to manipulate them is a valuable skill to learn for use in almost any area of …

4.1 Sigma Notation and Riemann Sums get the area of the whole region. When you use this approach with many sub-regions, it will be useful to have a notation for adding many values