Sigma Notation
In order to understand Riemann sums and integration theory correctly it is important to understand summations using sigma notation.
Definition (Sigma Notation) If
are real numbers such that
then the summation of these numbers written in sigma notation is
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and also using functional notation,
![]()
where
The
is called the index of summation, the
is called the
th term of the sum, and the upper and lower bounds of the summation are
and
respectively.
Example (Sigma Notation) Write the sum
in expanded form.
Solution. In expanded form, the sum is
![sigma notation _gr_15.gif]](pages/sigma-notation/Images/sigma-notation_gr_15.gif)
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Example (Sigma Notation) Write the sum
in expanded form.
Solution. In expanded form, the sum is
![sigma notation _gr_21.gif]](pages/sigma-notation/Images/sigma-notation_gr_21.gif)
![]()
![]()
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Example (Sigma Notation) Write the sum
in sigma notation.
Solution. We find that
![sigma notation _gr_27.gif]](pages/sigma-notation/Images/sigma-notation_gr_27.gif)
Example (Sigma Notation) Write the sum
in sigma notation.
Solution. In sigma notation, we have
![sigma notation _gr_30.gif]](pages/sigma-notation/Images/sigma-notation_gr_30.gif)
Example (Sigma Notation) Write the sum
![]()
in sigma notation.
Solution. We find that
![]()
![sigma notation _gr_34.gif]](pages/sigma-notation/Images/sigma-notation_gr_34.gif)
Example (Sigma Notation) Write the sum
![]()
in sigma notation.
Solution. We find that
![]()
![sigma notation _gr_38.gif]](pages/sigma-notation/Images/sigma-notation_gr_38.gif)
Sigma Notation
Published by Library of Math -- Online math organized by subject into topics.
Written by Smith, David A.
http://www.libraryofmath.com/sigma-notation.html


