Charlie's.

Today we took notes on the 'captial sigma'.
This is in chapter 13, i think section 6.
She gave us the definition of a sigma; which is, a sigma is a series written in condensed form.
For this you have the little capital sigma sign (it looks like a weird E)
On top of it is #, at the bottom is n=#, and on the right side is f(x).
Where # is the limits of summation, n is the index, and f(x) is the summand.

Examples:

#1:
6
E 2(x)+4
x=2
So you just plug this into the summand [which is 2(x) +4] starting with 2 and ending at 6, adding them inbetween.
2(2)+4 + 2(3)+4 + 2(4)+4 + 2(5)+4 + 2(6)+4
= 8 + 10 + 12 + 14 + 16
= 60

#2:
3
E (3-p)^2
p=-1
(3+1)^2 + (3-0)^2 + (3-1)^2 + (3-2)^2 + (3-3)^2
= 4^2 + 3^2 + 2^2 + 1^2 + 0^2
= 16 + 9 + 4 + 1 + 0
=30