7.16 problem 16

Internal problem ID [614]

Book: Elementary differential equations and boundary value problems, 10th ed., Boyce and DiPrima
Section: Chapter 3, Second order linear equations, 3.1 Homogeneous Equations with Constant Coefficients, page 144
Problem number: 16.
ODE order: 2.
ODE degree: 1.

CAS Maple gives this as type [[_2nd_order, _missing_x]]

\[ \boxed {4 y^{\prime \prime }-y=0} \] With initial conditions \begin {align*} [y \left (-2\right ) = 1, y^{\prime }\left (-2\right ) = -1] \end {align*}

Solution by Maple

Time used: 0.031 (sec). Leaf size: 21

dsolve([4*diff(y(x),x$2) -y(x) = 0,y(-2) = 1, D(y)(-2) = -1],y(x), singsol=all)
 

\[ y \left (x \right ) = -\frac {{\mathrm e}^{1+\frac {x}{2}}}{2}+\frac {3 \,{\mathrm e}^{-1-\frac {x}{2}}}{2} \]

Solution by Mathematica

Time used: 0.012 (sec). Leaf size: 25

DSolve[{4*y''[x]-y[x]==0,{y[-2]==1,y'[-2]==-1}},y[x],x,IncludeSingularSolutions -> True]
 

\[ y(x)\to -\frac {1}{2} e^{-\frac {x}{2}-1} \left (e^{x+2}-3\right ) \]