# Thread: Expressing work as a riemann sum

1. ## Expressing work as a riemann sum

I've attached a picture of the problem I'm working on. Now I know work is either force times distance or the integral from a to b of f(x)dx, and that F=kx, but it seems like with the information they give me in this problem there isn't enough to find any of the three!

I AM new to this type of problem and my professor kind of brushed over the topic very quickly so I don't feel very confident in it, if someone could point me in the right direction on one or two of these problems I think I'd be OK to do the rest myself. Thanks in advance!

2. OK, I solved the first part of the problem that I posted, but I've attached a problem directly related to the first. It's asking how much work would be done pulling the rope HALF the distance as the first situation. I don't understand why all the answer choices involve adding integrals when really you could just divide your former answer in half?

Could someone help me out?

3. Sorry, I posted a poor picture, here's the right one