SAGE Server
Jason Hill has been kind enough to maintain a SAGE server:
If you are on campus, you can create an account and view public worksheets.
Riemann sum Mathematica notebook
I created a little notebook to run in Mathematica that hopefully will help visualize Riemann sums. Simply put in the function you'd like to examine, and make sure [a,b] is in the domain of the function.
Nasty Calc 2 Problem | 2/21/2011
This is the set up for the particular version I saw today in the help lab, it should be readily adjusted for your specific problem:
A debt of $105,000 accrues 8% interest annually. If the payment at the end of every year is $10,500 plus the interest from the past year, find a formula for the yearly payment.
Year 1:
$$ \begin{align*} B_1 &= 105000\cdot 1.08,\\ P_1 &= 10500+.08\cdot 105000 = (.18)105000. \end{align*} $$ Year 2:
$$ \begin{align*} B_2 &= (B_1-P_1)\cdot 1.08 = (.9B_0)1.08,\\ P_2 &= .1B_0+(.9\cdot .08)B_0=(.172)B_0. \end{align*} $$ Year 3:
$$ \begin{align*} B_3 &= (B_2-P_2)\cdot 1.08 = (.8B_0)1.08,\\ P_3 &= .1B_0+(.8\cdot .08)B_0=(.164)B_0. \end{align*} $$
Hopefully this should hint at what a general formula will look like.