Posted by T.Gracken on August 20, 2002 at 13:23:57:
In Reply to: Re: riemann sum posted by Ryan on August 20, 2002 at 10:46:55:
: T. Gracken:
: I probably didn't explain what was throwing me off. I was having trouble following the sigma notation ( ex: i^2 = ((n)(n+1)(2n+1))/6 ) I didn't see how this just appeared in the explanation but i got it now.
I thought you wanted the whole lecture.
Yes, there are a few "formulas" that really help with sums.
the sum (as i goes from 1 to n) of k {where k is a constant}
the sum (as i goes from 1 to n) of i
the sum (as i goes from 1 to n) of i2
the sum (as i goes from 1 to n) of i3
...most teachers aren't cruel enough to have a sum with i to a higher power. The above sums can all be written in terms of n and should be in your textbook.