Updated date:

Dec 6, 2009

Maths - How to use SIGMA Notation - Manually and with a TI Calculator

Author:: expectus

So hopefully by the end of this you will understand how to use sigma if it ever comes up when you’re doing some maths at school or UNI. It’s quite common in UNI and if you’re like me and your brain isn’t built for maths hope this helps. Have a graphics calculator really speeds up the process to so I will go through how to enter an equation into your calculator. Most people use ti calculators so I will give a little example on how to use sigma on a ti calculator.

Sigma is simply an abbreviation or handy way to notate long sums.

For example

0 + 1 + 2 + 3 + 4 + 5 + 6 + 7 would be in sigma notation ( i = 0 ) at the bottom and 7 at the top of sigma

So the next step is to plug in every value for ( i ) into the term right of the sigma symbol and adding them up.

Another helpful explanation is The sum ( 1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 +10 + 11 + 12)

If you got this far and your still confused that’s alright I was ready to run out of the room screaming. Here's another example that should make it click for you

From the above picture we see a 5 above the sigma sign a (i = 0 ) below and ( i^2) to the side. The 5 on the top denotes how many numbers you will sum together, The i^2 denotes that you must square each value from zero to five and the ( i = 0) tells you the number you will start at in this case 0.

this method for texas instruments graphic calculators

had this pic on comp not sure where i go it from

SIGMA on the Calculator

SUM can be found by pressing 2nd STAT (LIST)

-> MATH #5 sum

SEQ can be found by pressing 2nd STAT (LIST)

-> OPS #5 seq

Hooray the end

that's it for the hub:) hope you enjoyed it probably didn't unless you needed to know how to use sigma but i hope it helps those who do.

Comments

austin on April 18, 2012:

for any programmers out there...this describes a for loop.

so the first example can be written like this:

for(i=0;i<12;x++)

{

sum+=x;

}

the second one:

for(i=0;i<5;i++)

{

sum+=(i^2)

}

(< is less than...because they wont allow inequity signs on a blog dedicated to math...-_-)

Grace on October 23, 2011:

Can you tell me how to use the summation notation on my TI-89 when the increment is less than 1? I haven't been able to find a single site that explains how to solve "sqrt(1+x^4) on the interval [0,1] with delta x=.1.

Tom on October 12, 2011:

It was helpful.Thanks....

alana on March 07, 2011:

WOW THANKS SO MUCH!!!!!! stupid calculator doesn't have a sigma sign..

chip on September 30, 2010:

that explanation was so simple, why cant they just put that in maths textbooks

Neville Mitchell on June 04, 2010:

Damn that was so easy on the calculator, if only i had found this site at the beginning of my course

yo on March 29, 2010:

thanks:)

expectus (author) from Land Downunder on January 11, 2010:

hehe glad it helped swifty, I had the exact same problem that's why I made this hub :)