What does the Sigma symbol mean in math?

The capital Sigma (Σ) symbol represents summation, which means adding a sequence of numbers together, often defined with lower and upper limits.

What is the LaTeX code for the Sigma summation symbol?

The LaTeX command for the summation symbol is \sum. For a lowercase sigma, the command is \sigma.

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Sigma Symbol (Σ)

The uppercase Greek letter Sigma (Σ) is used in mathematics to denote summation — the adding together of a series of numbers or terms.

Mathematical Definition & Usage

The Summation Operator

In algebra and calculus, Sigma acts as a loop instruction. It sums a set of numbers that follow a specific formula pattern. The variables underneath and above the symbol represent the start index and end index of the loop.

Example Formula

The sum of the first n integers can be written as:

\sum_{i=1}^{n} i = 1 + 2 + 3 + ... + n

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