# riemann sums

• Oct 8th 2008, 07:20 PM
amiv4
riemann sums
Calculate each of the following approximations for http://webwork.math.uwyo.edu/webwork...52d1574201.png.
LEFT(2) = got this
RIGHT(2) =
TRAP(2) = got this
MID(2) = got this

I cant seem to figure out the right one
• Oct 8th 2008, 07:33 PM
Jhevon
Quote:

Originally Posted by amiv4
Calculate each of the following approximations for http://webwork.math.uwyo.edu/webwork...52d1574201.png.
LEFT(2) = got this
RIGHT(2) =
TRAP(2) = got this
MID(2) = got this

I cant seem to figure out the right one

if you got the left one, why is the right one that much different. by the way the 2 means you made 2 subintervals right? so you have 2 rectangles.

so you let $x_0 = 0, ~x_1 = 2, \text{ and } x_2 = 4$

for the LEFT(2) you chose the height of your two rectangles to be $f(x_0)$ and $f(x_1)$, where $f(x) = \frac {-5}{(x + 1)^3}$

so for the RIGHT(2), do pretty much the same thing, except choose $f(x_1)$ and $f(x_2)$ for the height of your rectangles.
• Oct 8th 2008, 07:36 PM
amiv4
i did that and got 2(-.18159-.04)
but for some reason it says that aint right
• Oct 8th 2008, 07:45 PM
Jhevon
Quote:

Originally Posted by amiv4
i did that and got 2(-.18159-.04)
but for some reason it says that aint right

of course that isn't right. -0.18159 is not f(2)
• Oct 8th 2008, 07:47 PM
amiv4
oh shoot i switched two numbers