A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 5 years ago

Please someone.. I just need to know which method to use here.. Find the volume of the solid generated by revolving the described region about the given axis: The region in the first quadrant bounded above by the line y=4 and by the curve y=4sin(x) for the interval 0≤x≤π2 about the line y=4

  • This Question is Closed
  1. anonymous
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Anyone?

  2. TuringTest
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Disk method seems good to me.

  3. TuringTest
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I'm gonna assume your interval is\[0\le x\le\frac\pi 2\]your graph will be|dw:1327539383308:dw|it looks like the area of each disk will be\[dA=\pi r^2=\pi(4-4\sin x)^2dx=16\pi(1-2\sin x+\sin^2x)dx\]Being a little clever here we can use a trig identity and this becomes\[dA=16\pi[1-2\sin x+\frac1 2(1-\cos(2x)]dx\]\[dA=16\pi[\frac3 2-2\sin x-\cos(2x)]dx\]which we can integrate over our interval with a simple u-substitution.

  4. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.