50.3.4 problem 4

Internal problem ID [10148]
Book : Own collection of miscellaneous problems
Section : section 3.0
Problem number : 4
Date solved : Tuesday, September 30, 2025 at 07:05:13 PM
CAS classification : [[_2nd_order, _linear, _nonhomogeneous]]

\begin{align*} y^{\prime \prime }+y&=\sin \left (x \right ) \end{align*}

With initial conditions

\begin{align*} y^{\prime }\left (0\right )&=1 \\ \end{align*}

✓ Maple. Time used: 0.018 (sec). Leaf size: 20

ode:=diff(diff(y(x),x),x)+y(x) = sin(x); 
ic:=[D(y)(0) = 1]; 
dsolve([ode,op(ic)],y(x), singsol=all);
 

\[ y = \frac {\left (2 c_1 -x \right ) \cos \left (x \right )}{2}+\frac {3 \sin \left (x \right )}{2} \]

✓ Mathematica. Time used: 0.014 (sec). Leaf size: 42

ode=D[y[x],{x,2}]+y[x]==Sin[x]; 
ic={Derivative[1][y][0] == 1}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\begin{align*} y(x)&\to \cos (x) \int _0^x-\sin ^2(K[1])dK[1]+\frac {11 \sin (x)}{8}-\frac {1}{8} \sin (3 x)+c_1 \cos (x) \end{align*}

✓ Sympy. Time used: 0.058 (sec). Leaf size: 17

from sympy import * 
x = symbols("x") 
y = Function("y") 
ode = Eq(y(x) - sin(x) + Derivative(y(x), (x, 2)),0) 
ics = {Subs(Derivative(y(x), x), x, 0): 1} 
dsolve(ode,func=y(x),ics=ics)
 

\[ y{\left (x \right )} = \left (C_{1} - \frac {x}{2}\right ) \cos {\left (x \right )} + \frac {3 \sin {\left (x \right )}}{2} \]