1. Limited time only! Sign up for a free 30min personal 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!

Solving length of the curve

  1. Sep 20, 2009 #1
    The problem statement, all variables and given/known data

    Find the length of the curve x^(2/3)+y^(2/3) = 1 for x in the interval [0.1].

    The attempt at a solution

    y = (1-x)^(2/3)
    f'(x) = (4x^(-1/3) (1-x^(2/3))^(1/2))/9

    then i plugged it into arc length formula
    S sqrt(1+((4x^(-1/3) (1-x^(2/3))^(1/2))/9)^2 =

    S sqrt(1+((16x^(-2/3) (1-x^(2/3))/81) =

    S sqrt(1+((16x^(-2/3) -16)/81) =

    S sqrt(16x^(-2/3) +65))/81 =

    1/9 S sqrt(16x^(-2/3) +65) = ...

    then I got stuck.. I wasn't even sure if I was solving this question the right way.
    If I let u = (16x^(-2/3) +65), then whole bunch of weird numbers come out..

    thank you in advance
  2. jcsd
  3. Sep 20, 2009 #2
    You started with the wrong equation for y. Exponents are wrong or missing.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Discussions: Solving length of the curve
  1. Length of a curve? (Replies: 15)

  2. Length of Curve (Replies: 18)

  3. Length of a curve (Replies: 10)

  4. Length of A Curve (Replies: 32)