23.5.73 problem 73

Internal problem ID [6682]
Book : Ordinary differential equations and their solutions. By George Moseley Murphy. 1960
Section : Part II. Chapter 5. THE EQUATION IS LINEAR AND OF ORDER GREATER THAN TWO, page 410
Problem number : 73
Date solved : Friday, October 03, 2025 at 02:09:43 AM
CAS classification : [[_3rd_order, _with_linear_symmetries]]

\begin{align*} -y+x y^{\prime }-y^{\prime \prime }+x y^{\prime \prime \prime }&=0 \end{align*}

✓ Maple. Time used: 0.005 (sec). Leaf size: 16

ode:=-y(x)+x*diff(y(x),x)-diff(diff(y(x),x),x)+x*diff(diff(diff(y(x),x),x),x) = 0; 
dsolve(ode,y(x), singsol=all);
 

\[ y = c_1 x +c_2 \cos \left (x \right )+c_3 \sin \left (x \right ) \]

✓ Mathematica. Time used: 0.045 (sec). Leaf size: 21

ode=-y[x] + x*D[y[x],x] - D[y[x],{x,2}] + x*D[y[x],{x,3}] == 0; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\begin{align*} y(x)&\to c_1 x+c_3 \cos (x)-c_2 \sin (x) \end{align*}

✗ Sympy

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(x*Derivative(y(x), x) + x*Derivative(y(x), (x, 3)) - y(x) - Derivative(y(x), (x, 2)),0) 
ics = {} 
dsolve(ode,func=y(x),ics=ics)
 

NotImplementedError : The given ODE Derivative(y(x), x) - (-x*Derivative(y(x), (x, 3)) + y(x) + Deri