Transcript Summation Notation

SUMMATION NOTATION
This number tells us when
to stop (the last integer to
sub in).
This is the formula to
sub into
5
This sign means
to sum up each
of the terms in
the sequence
 3k  2
k 1
This number tells us what
integer to start subbing in
to create the terms in a
sequence
31  2
33  2
35  2
5  8  11  14  17
32  2
34  2
 55
Often we want to sum the terms in a sequence so
summation notation is a short-hand way express this.
If the top number is an n, write out the sequence summing
the terms with a … to the nth term:
3
 

k 0  2 
n
k
start by subbing in 0 for
the k in the formula
0
1
2
 3  3  3
 3
           
 2  2  2
 2
n
Finally, let’s see if we can go backwards. Given the sum
of the terms of the sequence, can we write it using
summation notation?
1  3  5  7   212 1
Does 2k - 1 generate
these terms subbing in 1
then 2 etc.?
12
this appears to be the
formula with a 12 subbed in
 2k  1
k 1
Acknowledgement
I wish to thank Shawna Haider from Salt Lake Community College, Utah
USA for her hard work in creating this PowerPoint.
www.slcc.edu
Shawna has kindly given permission for this resource to be downloaded
from www.mathxtc.com and for it to be modified to suit the Western
Australian Mathematics Curriculum.
Stephen Corcoran
Head of Mathematics
St Stephen’s School – Carramar
www.ststephens.wa.edu.au