7.6 problem 6

Internal problem ID [162]

Book: Differential equations and linear algebra, 3rd ed., Edwards and Penney
Section: Section 5.1, second order linear equations. Page 299
Problem number: 6.
ODE order: 2.
ODE degree: 1.

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

\[ \boxed {y^{\prime \prime }+y^{\prime }-6 y=0} \] With initial conditions \begin {align*} [y \left (0\right ) = 7, y^{\prime }\left (0\right ) = -1] \end {align*}

Solution by Maple

Time used: 0.0 (sec). Leaf size: 17

dsolve([diff(y(x),x$2)+diff(y(x),x)-6*y(x)=0,y(0) = 7, D(y)(0) = -1],y(x), singsol=all)
 

\[ y \left (x \right ) = \left (4 \,{\mathrm e}^{5 x}+3\right ) {\mathrm e}^{-3 x} \]

Solution by Mathematica

Time used: 0.012 (sec). Leaf size: 20

DSolve[{y''[x]+y'[x]-6*y[x]==0,{y[0]==7,y'[0]==-1}},y[x],x,IncludeSingularSolutions -> True]
                                                                                    
                                                                                    
 

\[ y(x)\to e^{-3 x} \left (4 e^{5 x}+3\right ) \]