The sum of two numbers is what we get when we add the two numbers together. This operation is called summation. There are a number of ways of writing sums, with the most common being:
- Addition ()
- Summation ()
- Sum = 0
- For I = M to N
- Sum = Sum + X(I)
- Next I (in Visual BASIC)
Sigma notation[change | change source]
Sigma notation is a mathematical notation to write long sums in a short way. Sigma notation uses the Greek letter Sigma (), and takes upper and lower bounds which tell us where the sum begins and where it ends. The lower bound usually has a variable (called the index, often denoted by , or ) along with a value, such as "". This tells us that the summation begins at 2, and goes up by 1 until it reaches the number on the top.
Properties[change | change source]
Applications[change | change source]
The concept of an integral is a limit of sums, with the area under a curve being defined as:
Related pages[change | change source]
References[change | change source]
- "Compendium of Mathematical Symbols". Math Vault. 2020-03-01. Retrieved 2020-08-16.
- Weisstein, Eric W. "Sum". mathworld.wolfram.com. Retrieved 2020-08-16.
- "Calculus I - Summation Notation". tutorial.math.lamar.edu. Retrieved 2020-08-16.
Further reading[change | change source]
- Nicholas J. Higham, "The accuracy of floating point summation", SIAM J. Scientific Computing 14 (4), 783–799 (1993).
Other websites[change | change source]
- Media related to Sum at Wikimedia Commons
- Sigma Notation on PlanetMath
- Derivation of Polynomials to Express the Sum of Natural Numbers with Exponents