refresher

definition
A sequence (or progression) is an ordered list of numbers (values).

Sequence: 2, 4, 6, 8 10, 12, 14
The numbers (or values) are called "terms" or "elements" of the sequence.
sequenceterms

definition
A series is the sum you get when you add all of the terms of a sequence.

Series: 2 + 4 + 6 + 8 + 10 + 12 + 14 = 56

When writing a series, a shorthand notation is used to represent the sum of a number of terms having a common form. This shorthand notation is referred to as "summation notation" or "sigma notation". The symbol used in the notation, , is the Greek capital letter sigma.

sigma56
Numbers are substituted into the expression (2i) starting with the first "i" value of "1" and continuing (counting by ones) until the "i" value reaches "7". All of these substitutions are then added, creating a series.
sigmapic

 

examples

seriesex1b
seriesex2
Note: parentheses are used when the value representing the sequence consists of more than one term. sumnotequal   because    SUMNOTEQUAL2
seriesex3
seriesex4


divider

ti84c
For calculator help with
summation notation
click here.


divider


NOTE: The re-posting of materials (in part or whole) from this site to the Internet is copyright violation
and is not considered "fair use" for educators. Please read the "Terms of Use".