7.4.9 problem 9

Internal problem ID [81]
Book : Elementary Differential Equations. By C. Henry Edwards, David E. Penney and David Calvis. 6th edition. 2008
Section : Chapter 1. First order differential equations. Section 1.5 (linear equations). Problems at page 54
Problem number : 9
Date solved : Saturday, March 29, 2025 at 04:30:31 PM
CAS classification : [_linear]

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

With initial conditions

\begin{align*} y \left (1\right )&=7 \end{align*}

✓ Maple. Time used: 0.022 (sec). Leaf size: 10

ode:=x*diff(y(x),x)-y(x) = x; 
ic:=y(1) = 7; 
dsolve([ode,ic],y(x), singsol=all);
 

\[ y = \left (\ln \left (x \right )+7\right ) x \]

✓ Mathematica. Time used: 0.024 (sec). Leaf size: 11

ode=x*D[y[x],x]-y[x]==x; 
ic={y[1]==7}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\[ y(x)\to x (\log (x)+7) \]

✓ Sympy. Time used: 0.164 (sec). Leaf size: 8

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(x*Derivative(y(x), x) - x - y(x),0) 
ics = {y(1): 7} 
dsolve(ode,func=y(x),ics=ics)
 

\[ y{\left (x \right )} = x \left (\log {\left (x \right )} + 7\right ) \]