A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 5 years ago

Find the points on the given curve where the tangent line is horizontal or vertical. r = 3cos(theta)

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

    Use y=rsin(theta) x=rcos(theta) Take dy/dx .. take it from here?

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

    yup got it thanks

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

    YEAAH!

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

    well i actually have to do it but haha your not completely right atm lemme see

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

    actually don't you use the polar curve formula of dy/dx = rcos(theta) + sin(theta) (dr/d(theta)) / -rsin(theta)+cos(theta) (dr/d(theta))? then just set top = 0 or the bottom = 0?

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

    So when your dx=0 you have a vertical tangent line. Actually for this equations there are alot of points where it should be vertical and the horizontal points aren't quite as easy because you have to solve something like 3(cos^2(theta)-sin^2(theta))=0

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

    yep thats exactly what you do, the formula you typed is just the product rule for derivatives

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

    actually not quite

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

    alrighty. easy enough. thanks =)

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

    yep :)

  11. 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.