Summation symbol #
The summation symbol can be used to shortcut long sums. The lower bound is denoted below the summation symbol and the upper bound above.
\[\sum_{i=1}^{10} i = 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 10\]A constant can be moved out of the summation:
\[\sum_{i=1}^{n} ci = c \sum_{i=1}^{n}i\]A summation over a constant \(c\) can also be simplified:
\[\sum_{i=1}^{n} c = nc\]