Having trouble graphing a Volume problem

  • Thread starter Thread starter BlackMamba
  • Start date Start date
  • Tags Tags
    Graphing Volume
BlackMamba
Messages
187
Reaction score
0
Hello again,

Once I get this graphed correctly, I don't see any problems as to why I couldn't solve it. But for now I have a question about graphing this volume problem.

The problem says to find the volume generated by rotating the region bounded by y=e^x, x=0, and y=\pi about the x-axis.

I have a picture of what I my graph would look like. The green curve is the line y=e^x, and the rust colored line is, x=0. My question is where do I graph y=\pi ? Is it as simple as placing the line at y = 3.14?

Thanks for taking a look. It is greatly appreciated.
 

Attachments

  • graph.gif
    graph.gif
    2.1 KB · Views: 607
Physics news on Phys.org
I still am unsure about this. I could use the help. Thanks.

Actually I think I got it. But if you could look at confirm or deny what I have come up with I would appreciate it.
 

Attachments

  • scan.gif
    scan.gif
    31.3 KB · Views: 591
Last edited:
I'd love to confirm what you have, however, for some reason the attachment is "pending approval." I can't view it.

Left boundary is a vertical line at x=0. Right and bottom boundary is y=e^x. Top boundary is y=pi. There's an intersection point where y=e^x and y=pi meet. It should look like a triangle. Then you rotate about the x-axis.

I didn't bother attaching a picture since attachments on this forum need some approval.
 
BlackMamba said:
...My question is where do I graph y=\pi ? Is it as simple as placing the line at y = 3.14?

Yes, it is as simple as placing a line parallel to the x-axis at y = 3.14.
 
Thanks fire and radou.

Fire ~ Your description is what my graph looks like so thanks again.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top