MATLAB: Solving Nonlinear system of differential equations using Matlab

nonlinear diffrenial_equationsnonlinerde

How can i solve this system,
u''=(w'^2)'
w''''=(u'w'+w'^3)'
I have a problem writing the following expressions (w'^2)' and (w'^3)' in the standard form of Matlab ode solvers
Thanks

Best Answer

  • u''=2w'*w''
    w''''=u''*w'+u'*w''+3w'^2*w''=5w'^2'w''+u'*w''
    

    ->

    u1'=u2
    w1'=w2
    w2'=w3
    w3'=w4
    u2'=2*w2*w3
    w4'=5*w2'^2*w3+u2*w3
    

    Here,

    u1=u, u2=u', w1=w, w2=w', w3=w'', w4=w'''.
    

    Best wishes

    Torsten.