64.11.45 problem 45
Internal
problem
ID
[13416]
Book
:
Differential
Equations
by
Shepley
L.
Ross.
Third
edition.
John
Willey.
New
Delhi.
2004.
Section
:
Chapter
4,
Section
4.3.
The
method
of
undetermined
coefficients.
Exercises
page
151
Problem
number
:
45
Date
solved
:
Wednesday, March 05, 2025 at 09:54:10 PM
CAS
classification
:
[[_2nd_order, _linear, _nonhomogeneous]]
\begin{align*} y^{\prime \prime }+6 y^{\prime }+13 y&=x \,{\mathrm e}^{-3 x} \sin \left (2 x \right )+x^{2} {\mathrm e}^{-2 x} \sin \left (3 x \right ) \end{align*}
✓ Maple. Time used: 0.004 (sec). Leaf size: 68
ode:=diff(diff(y(x),x),x)+6*diff(y(x),x)+13*y(x) = x*exp(-3*x)*sin(2*x)+x^2*exp(-2*x)*sin(3*x);
dsolve(ode,y(x), singsol=all);
\[
y = -\frac {3 \,{\mathrm e}^{-3 x} \left (\left (\frac {13 x^{2}}{12}-\frac {26 c_{1}}{3}-\frac {39}{16}\right ) \cos \left (2 x \right )+\left (x^{2}-\frac {2}{13} x -\frac {180}{169}\right ) {\mathrm e}^{x} \cos \left (3 x \right )+\frac {2 \left (x^{2}-\frac {41}{13} x +\frac {563}{338}\right ) {\mathrm e}^{x} \sin \left (3 x \right )}{3}-\frac {13 \sin \left (2 x \right ) \left (x +16 c_{2} \right )}{24}\right )}{26}
\]
✓ Mathematica. Time used: 0.415 (sec). Leaf size: 120
ode=D[y[x],{x,2}]+6*D[y[x],x]+13*y[x]==x*Exp[-3*x]*Sin[2*x]+x^2*Exp[-2*x]*Sin[3*x];
ic={};
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
\[
y(x)\to e^{-3 x} \left (\cos (2 x) \int _1^x-\cos (K[2]) K[2] \left (2 \cos (K[2])+e^{K[2]} (2 \cos (2 K[2])+1) K[2]\right ) \sin ^2(K[2])dK[2]+\sin (2 x) \int _1^x\frac {1}{2} \cos (2 K[1]) K[1] \left (2 \cos (K[1])+e^{K[1]} (2 \cos (2 K[1])+1) K[1]\right ) \sin (K[1])dK[1]+c_2 \cos (2 x)+c_1 \sin (2 x)\right )
\]
✓ Sympy. Time used: 0.952 (sec). Leaf size: 92
from sympy import *
x = symbols("x")
y = Function("y")
ode = Eq(-x**2*exp(-2*x)*sin(3*x) - x*exp(-3*x)*sin(2*x) + 13*y(x) + 6*Derivative(y(x), x) + Derivative(y(x), (x, 2)),0)
ics = {}
dsolve(ode,func=y(x),ics=ics)
\[
y{\left (x \right )} = \left (- \frac {x^{2} \sin {\left (3 x \right )}}{13} - \frac {3 x^{2} \cos {\left (3 x \right )}}{26} + \frac {41 x \sin {\left (3 x \right )}}{169} + \frac {3 x \cos {\left (3 x \right )}}{169} + \left (\left (C_{1} - \frac {x^{2}}{8}\right ) \cos {\left (2 x \right )} + \left (C_{2} + \frac {x}{16}\right ) \sin {\left (2 x \right )}\right ) e^{- x} - \frac {563 \sin {\left (3 x \right )}}{4394} + \frac {270 \cos {\left (3 x \right )}}{2197}\right ) e^{- 2 x}
\]