1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Volume by integration

  1. Oct 27, 2005 #1
    I'm supposed to find the volume of the figure that appears by rotating the follwing around the x-axis:
    [tex]y = e^x \cdot \sin (x) & x \in \left[ {0,\left. \pi \right]} \right.[/tex]
    This means (I think) that the function needs to be to the second power and multiplied by Pi in an integral. So the integral becomes
    [tex]
    \pi \int {e^{2x} \cdot \sin ^2 (x)dx}
    [/tex]
    I need hints on how to solve this integral, I've tried integration by parts but not really gotten anywhere...am I on the right track?
     
  2. jcsd
  3. Oct 27, 2005 #2
    here is a hint, maybe change sin squared into something more friendly.
     
    Last edited: Oct 27, 2005
  4. Oct 27, 2005 #3
    I tried to change it into 1-cos2x = 2(sinx)^2, but I didn't find it to make it any easier...was that what you thought about?
     
  5. Oct 27, 2005 #4
    yes, change (sinx)^2 = 1/2 - (1/2)cos2x. multiply your e function through and you will have 2 integrals that can be solved. the integral with (e^2x)(1/2 cos 2x) is going to need parts twice.
     
    Last edited: Oct 27, 2005
  6. Oct 27, 2005 #5
    I do believe you might be on to something there 1800bigk...thx!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Volume by integration
  1. Volume by Integration (Replies: 4)

  2. Integration By Volume (Replies: 5)

  3. Volume by integration (Replies: 1)

  4. Volume Integral (Replies: 3)

  5. Volume Integral (Replies: 11)

Loading...