Solution 13 to problem l1o35


Expressions | Parameters | Relevance | Back to problem l1o35

Expressions

The solution is given through the following expressions:

b74=0


b73=0


b72=0


         1     3
      - ----*a2 *a8*b1
         54
b71=-------------------
              4
            a1


         1    2
      - ---*a2 *a8*b1
         3
b70=------------------
             3
           a1


b69=0


         1    2
      - ---*a2 *a8*b1
         6
b68=------------------
             3
           a1


      - a2*a8*b1
b67=-------------
           2
         a1


      - a2*a8*b1
b66=-------------
           2
         a1


b65=0


b64=0


      - a2*a8*b1
b63=-------------
           2
         a1


b62=0


         1
      - ---*a2*a8*b1
         6
b61=-----------------
             2
           a1


      - a8*b1
b60=----------
        a1


      - 3*a8*b1
b59=------------
         a1


b58=0


b57=0


b56=0


b55=0


          1     5
      - -----*a2 *b1
         486
b54=-----------------
             5
           a1


b53=0


         5     4
      - ----*a2 *b1
         81
b52=----------------
            4
          a1


b51=0


b50=0


         5     3
      - ----*a2 *b1
         18
b49=----------------
            3
          a1


         5     3
      - ----*a2 *b1
         27
b48=----------------
            3
          a1


b47=0


b46=0


b45=0


b44=0


         5    2
      - ---*a2 *b1
         9
b43=---------------
            2
          a1


         5     2
      - ----*a2 *b1
         18
b42=----------------
            2
          a1


b41=0


b40=0


b39=0


b38=0


         1
      - ---*a2*b1
         6
b37=--------------
          a1


b36=0


b35=0


b34=0


b33=0


b32=0


b31=0


b30=0


b29=0


b28=0


      2    2
     ---*a2 *a8*b1
      9
b27=---------------
            3
          a1


      1    2
     ---*a2 *a8*b1
      3
b26=---------------
            3
          a1


     2*a2*a8*b1
b25=------------
          2
        a1


     2*a2*a8*b1
b24=------------
          2
        a1


     6*a2*a8*b1
b23=------------
          2
        a1


     a2*a8*b1
b22=----------
         2
       a1


     a2*a8*b1
b21=----------
         2
       a1


     6*a8*b1
b20=---------
       a1


     18*a8*b1
b19=----------
        a1


     12*a8*b1
b18=----------
        a1


     12*a8*b1
b17=----------
        a1


     8*a8*b1
b16=---------
       a1


     a8*b1
b15=-------
      a1


     6*a8*b1
b14=---------
       a2


     24*a8*b1
b13=----------
        a2


     18*a8*b1
b12=----------
        a2


b11=0


      5     4
     ----*a2 *b1
      81
b10=-------------
           4
         a1


      10    3
     ----*a2 *b1
      9
 b9=-------------
           3
         a1


     10    3
    ----*a2 *b1
     27
b8=-------------
          3
        a1


     5    2
    ---*a2 *b1
     3
b7=------------
         2
       a1


     50    2
    ----*a2 *b1
     9
b6=-------------
          2
        a1


     10    2
    ----*a2 *b1
     9
b5=-------------
          2
        a1


     10
    ----*a2*b1
     3
b4=------------
        a1


    5*a2*b1
b3=---------
      a1


     5
    ---*a2*b1
     3
b2=-----------
       a1


         1
      - ---*a2*a8
         6
a21=--------------
          a1


a20= - a8


a19=0


         1     3
      - ----*a2
         54
a18=-------------
           2
         a1


a17=0


         1    2
      - ---*a2
         6
a16=------------
         a1


a15=0


a14=0


        1
a13= - ---*a2
        6


a12=0


a11=0


a10=0


 a9=2*a8


a8=a8


    6*a1*a8
a7=---------
      a2


    6*a1*a8
a6=---------
      a2


a5=0


     1    2
    ---*a2
     3
a4=---------
      a1


a3=a2


Parameters

Apart from the condition that they must not vanish to give a non-trivial solution and a non-singular solution with non-vanishing denominators, the following parameters are free:
 b1,a8,a2,a1

Relevance for the application:

The solution given above tells us that the system {u_s, v_s} is a higher order symmetry for the lower order system {u_t,v_t} where u=u(t,x) is a scalar function, v=v(t,x) is a vector function of arbitrary dimension and f(..,..) is the scalar product between two such vectors:
/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\

          2               2       2      2                         1       3  2
u =(u  *a1 *a2 + u  *a1*a2 *u + u  *a1*a2  + u *f(v,v)*a1*a2*a8 + ---*u *a2 *u
 t   3x           2x             x            x                    3   x

                    2                   2
     + 6*f(v ,v )*a1 *a8 + 6*f(v,v  )*a1 *a8 + 2*f(v,v )*a1*a2*a8*u)/(a1*a2)
            x  x                  2x                  x

        1        2         1          2                 2
v =( - ---*u  *a1 *a2*v - ---*u *a1*a2 *u*v - f(v,v )*a1 *a8*v
 t      6   2x             6   x                   x

        1                         1     3  3      2
     - ---*f(v,v)*a1*a2*a8*u*v - ----*a2 *u *v)/a1
        6                         54

          4          5        3   2                   3   2
u =(u  *a1 *a2*b1 + ---*u  *a1 *a2 *b1*u + 5*u  *u *a1 *a2 *b1
 s   5x              3   4x                   3x  x

                    3             10        2   3     2    10     2   3   2
     + u  *f(v,v)*a1 *a2*a8*b1 + ----*u  *a1 *a2 *b1*u  + ----*u   *a1 *a2 *b1
        3x                        9    3x                  3    2x

        50           2   3                        3
     + ----*u  *u *a1 *a2 *b1*u + 8*u  *f(v,v )*a1 *a2*a8*b1
        9    2x  x                   2x      x

                    2   2            10           4     3    5    3   2   3
     + u  *f(v,v)*a1 *a2 *a8*b1*u + ----*u  *a1*a2 *b1*u  + ---*u  *a1 *a2 *b1
        2x                           27   2x                 3   x

         2          2   2          10    2      4     2
     + u  *f(v,v)*a1 *a2 *a8*b1 + ----*u  *a1*a2 *b1*u
        x                          9    x

                        3                             3
     + 12*u *f(v ,v )*a1 *a2*a8*b1 + 12*u *f(v,v  )*a1 *a2*a8*b1
           x    x  x                     x      2x

                      2   2            1                 3        2
     + 6*u *f(v,v )*a1 *a2 *a8*b1*u + ---*u *f(v,v)*a1*a2 *a8*b1*u
          x      x                     3   x

        5        5     4                   4                        4
     + ----*u *a2 *b1*u  + 18*f(v  ,v  )*a1 *a8*b1 + 24*f(v ,v  )*a1 *a8*b1
        81   x                   2x  2x                    x  3x

                      3                           2   2        2
     + 18*f(v ,v  )*a1 *a2*a8*b1*u + 2*f(v ,v )*a1 *a2 *a8*b1*u
             x  2x                        x  x

                    4                      3
     + 6*f(v,v  )*a1 *a8*b1 + 6*f(v,v  )*a1 *a2*a8*b1*u
              4x                     3x

                    2   2        2    2               3        3     4
     + 2*f(v,v  )*a1 *a2 *a8*b1*u  + ---*f(v,v )*a1*a2 *a8*b1*u )/(a1 *a2)
              2x                      9       x

        1        4            5         3   2           5           3   2
v =( - ---*u  *a1 *a2*b1*v - ----*u  *a1 *a2 *b1*u*v - ---*u  *u *a1 *a2 *b1*v
 s      6   4x                18   3x                   9   2x  x

        1               3               5         2   3     2
     - ---*u  *f(v,v)*a1 *a2*a8*b1*v - ----*u  *a1 *a2 *b1*u *v
        6   2x                          27   2x

        5     2   2   3                       3
     - ----*u  *a1 *a2 *b1*u*v - u *f(v,v )*a1 *a2*a8*b1*v
        18   x                    x      x

        1              2   2              5           4     3
     - ---*u *f(v,v)*a1 *a2 *a8*b1*u*v - ----*u *a1*a2 *b1*u *v
        6   x                             81   x

                     4                      3
     - 3*f(v ,v  )*a1 *a8*b1*v - f(v ,v )*a1 *a2*a8*b1*u*v
            x  2x                   x  x

                  4                      3
     - f(v,v  )*a1 *a8*b1*v - f(v,v  )*a1 *a2*a8*b1*u*v
            3x                     2x

        1            2   2        2      1               3        3
     - ---*f(v,v )*a1 *a2 *a8*b1*u *v - ----*f(v,v)*a1*a2 *a8*b1*u *v
        3       x                        54

         1     5     5      5
     - -----*a2 *b1*u *v)/a1
        486