1. Not finding help here? Sign up for a free 30min 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!

Differential equation

  1. Mar 19, 2013 #1
    Hello

    I need help with the following differential equation:

    [tex](1-\frac{gh}{c^2}) A(u) - \frac{h^2}{3} A''(u) - \frac{3}{2h} A(u)^2 =0 [/tex]

    with [tex]g,h,c=constant[/tex]

    the answer has a [tex] \sech^2 [/tex] with [tex]A(0)=A_0[/tex] and [tex]A'(0)=0[/tex]

    thanksution[/b]
     
  2. jcsd
  3. Mar 19, 2013 #2

    tiny-tim

    User Avatar
    Science Advisor
    Homework Helper

    hello alejandrito29! :smile:

    that's A'' = pA - qA2 with p and q constant

    start by multiplying both sides by A', and then integrating :wink:
     
  4. Mar 19, 2013 #3
    differential equation1

    i have the differential equation

    [tex] A''=p A - q A^2 [/tex]

    i multiplying by A' both sides then

    [tex] A' A''=p A A' - q A^2A' [/tex] then

    [tex] (\frac{1}{2}(A')^2)'=\frac{p}{2} (A^2)' - \frac{q}{3} (A^3)' [/tex]
    then i integer and:

    [tex] (\frac{1}{2}(A')^2)=\frac{p}{2} (A^2) - \frac{q}{3} (A^3) [/tex]

    but i write in maple this differential equation and i dont obtain the solution. This solution must have of the way [tex] A(x)=k_1 sech ^2 (k_2 x) [/tex]

    help please
     
    Last edited: Mar 19, 2013
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Differential equation
  1. Differential equations (Replies: 1)

  2. Differential equation (Replies: 4)

  3. Differential Equation (Replies: 12)

  4. Differential Equations (Replies: 1)

Loading...