2.23 problem problem 49

Internal problem ID [307]

Book: Differential equations and linear algebra, 4th ed., Edwards and Penney
Section: Section 5.3, Higher-Order Linear Differential Equations. Homogeneous Equations with Constant Coefficients. Page 300
Problem number: problem 49.
ODE order: 4.
ODE degree: 1.

CAS Maple gives this as type [[_high_order, _missing_x]]

Solve \begin {gather*} \boxed {y^{\prime \prime \prime \prime }-y^{\prime \prime \prime }-y^{\prime \prime }-y^{\prime }-2 y=0} \end {gather*} With initial conditions \begin {align*} [y \relax (0) = 0, y^{\prime }\relax (0) = 0, y^{\prime \prime }\relax (0) = 0, y^{\prime \prime \prime }\relax (0) = 15] \end {align*}

Solution by Maple

Time used: 0.016 (sec). Leaf size: 23

dsolve([diff(y(x),x$4)=diff(y(x),x$3)+diff(y(x),x$2)+diff(y(x),x)+2*y(x),y(0) = 0, D(y)(0) = 0, (D@@2)(y)(0) = 0, (D@@3)(y)(0) = 15],y(x), singsol=all)
 

\[ y \relax (x ) = {\mathrm e}^{2 x}-\frac {5 \,{\mathrm e}^{-x}}{2}-\frac {9 \sin \relax (x )}{2}+\frac {3 \cos \relax (x )}{2} \]

Solution by Mathematica

Time used: 0.003 (sec). Leaf size: 33

DSolve[{y'''[x]==y[x],{y[0]==1,y'[0]==0,y''[0]==0}},y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \frac {1}{3} \left (e^x+2 e^{-x/2} \cos \left (\frac {\sqrt {3} x}{2}\right )\right ) \\ \end{align*}