73.14.4 problem 21.6 (ii)

Internal problem ID [15414]
Book : Ordinary Differential Equations. An introduction to the fundamentals. Kenneth B. Howell. second edition. CRC Press. FL, USA. 2020
Section : Chapter 21. Nonhomogeneous equations in general. Additional exercises page 391
Problem number : 21.6 (ii)
Date solved : Tuesday, January 28, 2025 at 07:54:53 AM
CAS classification : [[_2nd_order, _with_linear_symmetries]]

\begin{align*} y^{\prime \prime }+2 y^{\prime }-8 y&=8 x^{2}-3 \end{align*}

With initial conditions

\begin{align*} y \left (0\right )&=1\\ y^{\prime }\left (0\right )&=-3 \end{align*}

Solution by Maple

Time used: 0.170 (sec). Leaf size: 32

dsolve([diff(y(x),x$2)+2*diff(y(x),x)-8*y(x)=8*x^2-3,y(0) = 1, D(y)(0) = -3],y(x), singsol=all)
 
\[ y = \frac {\left (-4 x^{2} {\mathrm e}^{4 x}+{\mathrm e}^{6 x}-2 \,{\mathrm e}^{4 x} x +3\right ) {\mathrm e}^{-4 x}}{4} \]

Solution by Mathematica

Time used: 0.016 (sec). Leaf size: 34

DSolve[{D[y[x],{x,2}]+2*D[y[x],x]-8*y[x]==8*x^2-3,{y[0]==1,Derivative[1][y][0] ==-3}},y[x],x,IncludeSingularSolutions -> True]
 
\[ y(x)\to \frac {1}{4} e^{-4 x} \left (-2 e^{4 x} x (2 x+1)+e^{6 x}+3\right ) \]