A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

marigirl

  • one year ago

Can you help me find an expression for h please

  • This Question is Closed
  1. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    1 Attachment
  2. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    SO far i have \[\frac{ 40-x }{ r }=\frac{ 40 }{ 20 }\]

  3. phi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    assuming h is the height of the cylinder

  4. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    What must the radius of the cylinder be to give the cylinder the maximum volume is my question..

  5. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    \[v=\pi r^2 h\] so an expression to sub into h

  6. phi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    I am not awake! the proportion is \[ \frac{40-h}{r}= \frac{40}{20} \]

  7. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    ok great so i was on the right track. ill go ahead and differentiate now :)

  8. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    why did u choose 40-h .....where as i did 40-x

  9. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    or are we talking about the same things?

  10. phi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    it depends what you mean by "x" I used h because h is the height of the cylinder

  11. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    so then when you did 40-h you meant 40-height of cylinder...so we are left with the top part of cylinder

  12. phi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    |dw:1444303521277:dw|

  13. phi
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    once we have that relation we can solve for h \[ \frac{40-h}{r}= 2 \\ 40-h= 2r \\ h= 40-2r \]

  14. marigirl
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    oh yup i get it now. thanks heaps!

  15. 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.