Sigma is the upper case letter S in Greek. And S stands for S um. I love Sigma, it is fun to use, and can do many clever things. So means to sum things up ... Sum whatever is after the Sigma:

Sigma notation is a structured way to write large sums concisely. It uses the symbol ∑ and typically looks like ∑ i = 1 n a i, meaning to sum the terms a 1 through a n using the specified …

Sigma notation (which is also known as summation notation) is the easiest way of writing a smaller or longer sum using the sigma symbol ∑, the general formula of the terms, and the index.

Summation notation (or sigma notation) allows us to write a long sum in a single expression. This is the sigma symbol: ∑ . It tells us that we are summing something. Notice how we substituted …

Oct 21, 2025 · Explore sigma notation with clear definitions, formulas, properties, and solved examples. Great for students and math learners.

Jun 20, 2025 · Learn about using sigma notation for summations for your A level maths exam. This revision note covers the key concepts and worked examples.

The summation of a specified number of terms of a sequence (a series) can also be represented in a compact form, called summation notation, or sigma notation. The Greek capital letter …