11.10 problem 10

Internal problem ID [228]

Book: Differential equations and linear algebra, 3rd ed., Edwards and Penney
Section: Section 5.5, Nonhomogeneous equations and undetermined coefficients Page 351
Problem number: 10.
ODE order: 2.
ODE degree: 1.

CAS Maple gives this as type [[_2nd_order, _linear, _nonhomogeneous]]

\[ \boxed {y^{\prime \prime }+9 y=2 \cos \left (3 x \right )+3 \sin \left (3 x \right )} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 30

dsolve(diff(y(x),x$2)+9*y(x)=2*cos(3*x)+3*sin(3*x),y(x), singsol=all)
 

\[ y \left (x \right ) = \frac {\left (18 c_{1} -9 x +2\right ) \cos \left (3 x \right )}{18}+\frac {\sin \left (3 x \right ) \left (x +3 c_{2} \right )}{3} \]

Solution by Mathematica

Time used: 0.231 (sec). Leaf size: 39

DSolve[y''[x]+9*y[x]==2*Cos[3*x]+3*Sin[3*x],y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to \left (-\frac {x}{2}+\frac {1}{9}+c_1\right ) \cos (3 x)+\frac {1}{12} (4 x+1+12 c_2) \sin (3 x) \]