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Nonlinear differential equation

DSolve[{x^3*y''''[x] +
12*x^2* y'''[x] +
36*x* y''[x] +
24 y'[x] + 60*x^3*(7 - 18* x^2 + 3* x^8)* (y[x])^9 ? 0,
y[0] ? 1, y'[0] ? 0, y'' ? 0, y'''[0] ? 0}, y[x], x]

I want to solve this question.i need its exact solution (its exact solution exists). Mathematica gives "DSolve::dvnoarg : The function y appears with no arguments. ?"

Please help

Attachments:
POSTED BY: Mariam Sultana
8 Replies

Seems to be very difficult. At least you can get an impression of the solution by a numerical method....

Attachments:
POSTED BY: Hans Dolhaine

Plz Mathematica team help me

POSTED BY: Mariam Sultana

It appears that Mathematica cannnot solve it symbolically.

In[5]:= DSolve[{y''''[x] + 12/x y'''[x] + 36/x^2 y''[x] + 
    24/x^3 y'[x] + 60 (7 - 18 x^4 + 3 x^8) y[x]^9 == 0, y[0] == 1, 
  y'[0] == 0, y''[0] == 0, y'''[0] == 0}, y[x], x]

Out[5]= DSolve[{60 (7 - 18 x^4 + 3 x^8) y[x]^9 + (
    24 Derivative[1][y][x])/x^3 + (36 (y^\[Prime]\[Prime])[x])/x^2 + (
    12 
\!\(\*SuperscriptBox[\(y\), 
TagBox[
RowBox[{"(", "3", ")"}],
Derivative],
MultilineFunction->None]\)[x])/x + 
\!\(\*SuperscriptBox[\(y\), 
TagBox[
RowBox[{"(", "4", ")"}],
Derivative],
MultilineFunction->None]\)[x] == 0, y[0] == 1, 
  Derivative[1][y][0] == 0, (y^\[Prime]\[Prime])[0] == 0, 
\!\(\*SuperscriptBox[\(y\), 
TagBox[
RowBox[{"(", "3", ")"}],
Derivative],
MultilineFunction->None]\)[0] == 0}, y[x], x]
POSTED BY: Frank Kampas

Sir please find attached file.Its a fourth order non-linear differential equation.I unable to solve this equation,Please help

enter image description here

POSTED BY: Mariam Sultana

Easier to diagnose problems when they are posted in code sample windows (first icon). However, I'm guessing you've got uncleared expressions that are resulting in the True that you see.

POSTED BY: Frank Kampas

I write argument of y'' but now the error is "

DSolve::deqn: Equation or list of equations expected instead of True
 in the first argument {60 x^3 (7-18 x^2+3 x^8) y[x]^9+24 (y^\[Prime])[x]
+36 x (y^\[Prime]\[Prime])[x]+12 x^2 (y^(3))[x]+x^3 (y^(4))[x]==0,True,0,True,True}. >>
POSTED BY: Mariam Sultana

I write argument of y'' but now the error is "

DSolve::deqn: Equation or list of equations expected instead of True
in the first argument {60 x^3 (7-18 x^2+3 x^8) y[x]^9+24 (y^\[Prime])[x]
+36 x (y^\[Prime]\[Prime])[x]+12 x^2 (y^(3))[x]+x^3 (y^(4))[x]==0,True,0,True,True}. >>
POSTED BY: Mariam Sultana

Your initial condition for y'' has no argument.

POSTED BY: Frank Kampas
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