10.40 problem 40

Internal problem ID [11770]

Book: Differential Equations by Shepley L. Ross. Third edition. John Willey. New Delhi. 2004.
Section: Chapter 4, Section 4.2. The homogeneous linear equation with constant coefficients. Exercises page 135
Problem number: 40.
ODE order: 3.
ODE degree: 1.

CAS Maple gives this as type [[_3rd_order, _missing_x]]

\[ \boxed {y^{\prime \prime \prime }-2 y^{\prime \prime }+4 y^{\prime }-8 y=0} \] With initial conditions \begin {align*} [y \left (0\right ) = 2, y^{\prime }\left (0\right ) = 0, y^{\prime \prime }\left (0\right ) = 0] \end {align*}

Solution by Maple

Time used: 0.015 (sec). Leaf size: 19

dsolve([diff(y(x),x$3)-2*diff(y(x),x$2)+4*diff(y(x),x)-8*y(x)=0,y(0) = 2, D(y)(0) = 0, (D@@2)(y)(0) = 0],y(x), singsol=all)
 

\[ y \left (x \right ) = {\mathrm e}^{2 x}-\sin \left (2 x \right )+\cos \left (2 x \right ) \]

Solution by Mathematica

Time used: 0.003 (sec). Leaf size: 21

DSolve[{y'''[x]-2*y''[x]+4*y'[x]-8*y[x]==0,{y[0]==2,y'[0]==0,y''[0]==0}},y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to e^{2 x}-\sin (2 x)+\cos (2 x) \]