11.17 problem 17

Internal problem ID [2156]

Book: Differential Equations by Alfred L. Nelson, Karl W. Folley, Max Coral. 3rd ed. DC heath. Boston. 1964
Section: Exercise 19, page 86
Problem number: 17.
ODE order: 3.
ODE degree: 1.

CAS Maple gives this as type [[_3rd_order, _linear, _nonhomogeneous]]

\[ \boxed {y^{\prime \prime \prime }-4 y^{\prime \prime }+y^{\prime }-4 y=\sin \left (x \right ) {\mathrm e}^{4 x}} \]

Solution by Maple

Time used: 0.015 (sec). Leaf size: 31

dsolve(diff(y(x),x$3)-4*diff(y(x),x$2)+diff(y(x),x)-4*y(x)=exp(4*x)*sin(x),y(x), singsol=all)
 

\[ y \left (x \right ) = \frac {\left (40 c_{3} -2 \cos \left (x \right )-\sin \left (x \right )\right ) {\mathrm e}^{4 x}}{40}+\cos \left (x \right ) c_{1} +\sin \left (x \right ) c_{2} \]

Solution by Mathematica

Time used: 0.098 (sec). Leaf size: 44

DSolve[y'''[x]-4*y''[x]+y'[x]-4*y[x]==Exp[4*x]*Sin[x],y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to c_3 e^{4 x}+\left (-\frac {e^{4 x}}{20}+c_1\right ) \cos (x)+\left (-\frac {e^{4 x}}{40}+c_2\right ) \sin (x) \]