Results 1 to 3 of 3
Like Tree1Thanks
  • 1 Post By Prove It

Math Help - Evaluating parametic derivative

  1. #1
    Newbie
    Joined
    Sep 2012
    From
    Manhattan
    Posts
    12
    Thanks
    1

    Evaluating parametic derivative

    u = 3t-1 t = v2-7v w = 7/v ; find du/dw at w= -7

    I tried solving for du/dt and got 3
    dt/dv = 2v-7 and dw/dv = -7/v^2

    I'm not sure how the w = -7 is supposed to work with this because if i just plug it in to the third equation i get a v value which i don't need

    I already know that du/dw is essentially du/dt / dw/dt. I have du/dt.

    Question: How do I solve for dw/dt? Any help appreciated, thanks!
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor
    Prove It's Avatar
    Joined
    Aug 2008
    Posts
    11,786
    Thanks
    1570

    Re: Evaluating parametic derivative

    \displaystyle \begin{align*} \frac{du}{dw} = \frac{du}{dt} \cdot \frac{dt}{dv} \cdot \frac{dv}{dw} \end{align*}.

    Notice that \displaystyle \begin{align*} w = \frac{7}{v} \implies v = \frac{7}{w} \end{align*}.
    Thanks from mikewezyk
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Newbie
    Joined
    Sep 2012
    From
    Manhattan
    Posts
    12
    Thanks
    1

    Re: Evaluating parametic derivative

    Thanks so much!!!
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Find the limit by evaluating the derivative only
    Posted in the Pre-Calculus Forum
    Replies: 3
    Last Post: July 25th 2012, 10:15 AM
  2. Finding the Parametic equation
    Posted in the Advanced Algebra Forum
    Replies: 4
    Last Post: November 2nd 2010, 02:36 AM
  3. Parametic curves in 2DD problems
    Posted in the Calculus Forum
    Replies: 3
    Last Post: October 21st 2010, 12:52 AM
  4. Evaluating Partial Derivative
    Posted in the Calculus Forum
    Replies: 9
    Last Post: June 28th 2010, 02:22 PM
  5. Evaluating a Derivative at a Given point
    Posted in the Calculus Forum
    Replies: 3
    Last Post: June 14th 2009, 02:27 PM

Search Tags


/mathhelpforum @mathhelpforum