A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 5 years ago

i need someone to explaim how to figure surface areas of a cone

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

    radius 7 height 2

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

    Is it closed on the bottom of the cone? If so, the surface area is:\[SA = \pi*r*s+\pi*r^2\] where "s" is the length from the tip of the cone to the outer edge of the base. If it's an open cone, you can get rid of the pi*r^2 term.

  3. amistre64
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    circumference of the base integrated thru the height, if that makes sense :)

  4. amistre64
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    height for any given piece is (2-y) circumference for any given piece is (2pi(x)) x = -(7/2) y So; 2pi(-7/1)y dy from 0 to 2.... might need a second pair of eyes on that tho :)

  5. amistre64
    • 5 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    .... -7pi (S) (y)(2-y) dy | 0,2 -7pi (S) 2y - y^2 dy | 0,2 -7pi; y^2 - (y^3)/3 | 0,2 .... only (2) matters -7pi; 2^2 - (2^3)/3 -7pi (4 - (8/3)) = (12/3 - 8/3) -7pi (4/3) = -28pi/3 ; we can toss the (-) because it just means we used the wrong "side" and we are left with.. 28pi/3 ..... of which I have no idea if ii did it correctly :)

  6. 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.