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!

Finding d^2y/dx^2 for a parametrized curve

  1. Mar 23, 2010 #1
    Find d2y/dx2 as a function of t if x = t - t2 and y = t - t3

    Ok, so this basically means we're going to take the second derivative of y with respect to t over the derivative of x with respect to t.

    So the second derivative of y would be.

    [2 - 6t + 6t2]/(1 - 2t)2

    Now, we just put that over the first derivative of x which is 1 - 2t so we get:

    [[2 - 6t + 6t2]/(1 - 2t)2]/(1 - 2t)

    =

    (2 - 6t + 6t2)/(1 - 2t)3

    Correct or incorrect?
     
  2. jcsd
  3. Mar 23, 2010 #2

    gabbagabbahey

    User Avatar
    Homework Helper
    Gold Member

    Why do you think this?

    [tex]\frac{d^2y}{dx^2}=\frac{d}{dx}\left(\frac{dy}{dx}\right)[/tex]

    Use the chain rule

    [tex]\frac{d}{dx}=\frac{dt}{dx}\frac{d}{dt}=\frac{1}{x'(t)}\frac{d}{dt}[/tex]
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Finding d^2y/dx^2 for a parametrized curve
Loading...