Summarize this article:
Last updated on September 10, 2025
Summation is a fundamental concept in mathematics with various properties that simplify the process of adding sequences of numbers. These properties help students analyze and solve problems related to series and sequences. The properties of summation include linearity, commutativity, and more. Understanding these properties makes it easier to manipulate and evaluate sums. Now let us learn more about the properties of summation.
The properties of summation are essential for understanding and working with sequences and series. These properties are derived from mathematical principles and facilitate the simplification and evaluation of sums. There are several properties of summation, and some of them are mentioned below:
Students can sometimes confuse and make mistakes while learning the properties of summation. To avoid such confusion, we can follow these tips and tricks:
Students should remember that linearity allows the separation of sums. Failing to recognize this can lead to incorrect simplification of expressions.
Using linearity, we split the sum: \[\sum_{i=1}^n (2i + 3) = \sum_{i=1}^n 2i + \sum_{i=1}^n 3\] \(\sum_{i=1}^n 2i = 2\sum_{i=1}^n i = 2 \cdot \frac{n(n+1)}{2} = n(n+1)\) \(\sum_{i=1}^n 3 = 3n\) Thus, \(\sum_{i=1}^n (2i + 3) = n(n+1) + 3n\).
A series is given by \(\sum_{i=1}^4 (i^2 - i)\). Evaluate this sum.
The sum is 14.
Calculate each term: \((1^2 - 1) + (2^2 - 2) + (3^2 - 3) + (4^2 - 4) = 0 + 2 + 6 + 6 = 14\) Thus, the sum is 14.
If \(\sum_{i=1}^n a_i = 20\) and \(\sum_{i=1}^n b_i = 15\), what is \(\sum_{i=1}^n (a_i + b_i)\)?
The sum is 35.
Using linearity, \(\sum_{i=1}^n (a_i + b_i) = \sum_{i=1}^n a_i + \sum_{i=1}^n b_i = 20 + 15 = 35\).
For the series \(\sum_{i=1}^n 5\), express the sum in terms of \(n\).
The sum is \(5n\).
Using the constant factor property, \(\sum_{i=1}^n 5 = 5 \cdot \sum_{i=1}^n 1 = 5n\).
Evaluate the telescoping series \(\sum_{i=1}^5 (i - (i-1))\).
The sum is 5.
Students often make errors when applying the properties of summation.
Here are some common mistakes and how to avoid them.
Hiralee Lalitkumar Makwana has almost two years of teaching experience. She is a number ninja as she loves numbers. Her interest in numbers can be seen in the way she cracks math puzzles and hidden patterns.
: She loves to read number jokes and games.