9.15 problem 29

Internal problem ID [2101]

Book: Differential Equations by Alfred L. Nelson, Karl W. Folley, Max Coral. 3rd ed. DC heath. Boston. 1964
Section: Exercise 17, page 78
Problem number: 29.
ODE order: 3.
ODE degree: 1.

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

\[ \boxed {y^{\prime \prime \prime }-7 y^{\prime }+6 y=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 23

dsolve(diff(y(x),x$3)-7*diff(y(x),x)+6*y(x)=0,y(x), singsol=all)
 

\[ y \left (x \right ) = \left (c_{1} {\mathrm e}^{5 x}+c_{3} {\mathrm e}^{4 x}+c_{2} \right ) {\mathrm e}^{-3 x} \]

Solution by Mathematica

Time used: 0.003 (sec). Leaf size: 28

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

\[ y(x)\to c_1 e^{-3 x}+c_2 e^x+c_3 e^{2 x} \]