Sum and product in LaTeX
A sum is written with \sum and a product with \prod. In display math the limits go above and below the symbol; in a line of text they sit beside it so the line spacing stays even.
Sum
\sum_{i=1}^{n} x_iArithmetic mean
\bar{x} = \frac{1}{n} \sum_{i=1}^{n} x_iProduct
n! = \prod_{k=1}^{n} kCommon mistakes
- Using the capital letter \Sigma instead of \sum: it looks similar but has the wrong size and no room for limits.
See also
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