Results 1 to 2 of 2

Math Help - Mathematica help - diferential eq

  1. #1
    Newbie
    Joined
    Oct 2008
    Posts
    1

    Mathematica help - diferential eq

    Hi! I want to compute a partial derivative of the equation (please find it
    attached) with respect to the variable x:

    ImageShack - Hosting :: diffeqyi0.png

    How can i do that with Mathematica? Many thanks
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Newbie
    Joined
    Oct 2008
    Posts
    12
    I think what you will want to do is to write x as x[t] and j as j[t], so the equation would be:
    x''[t]1/(M+m Sin[j[t]]^2) *(m Sin[j[t]] (g Cos[j[t]]+ l j'[t]^2)-D x'[t]+F u)
    and to take the partial derivative with respect to x, you would write:
    D[x''[t]1/(M+m Sin[j[t]]^2) *(m Sin[j[t]] (g Cos[j[t]]+ l j'[t]^2)-D x'[t]+F u),x]
    which gives
    x(3)[t]=(D x''[t])/(M+m Sin[j[t]]2)
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. help me in Mathematica
    Posted in the Math Software Forum
    Replies: 2
    Last Post: May 18th 2010, 01:26 AM
  2. Mathematica
    Posted in the Math Software Forum
    Replies: 2
    Last Post: March 24th 2010, 07:13 AM
  3. Mathematica Help
    Posted in the Math Software Forum
    Replies: 1
    Last Post: March 5th 2010, 07:12 AM
  4. values which satisfy diferential equation
    Posted in the Differential Equations Forum
    Replies: 3
    Last Post: August 19th 2009, 11:08 AM
  5. Diferential equations
    Posted in the Differential Equations Forum
    Replies: 7
    Last Post: March 2nd 2009, 12:17 AM

Search Tags


/mathhelpforum @mathhelpforum