9.4 problem 1(d)

Internal problem ID [5985]

Book: An introduction to Ordinary Differential Equations. Earl A. Coddington. Dover. NY 1961
Section: Chapter 2. Linear equations with constant coefficients. Page 83
Problem number: 1(d).
ODE order: 5.
ODE degree: 1.

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

\[ \boxed {y^{\left (5\right )}+2 y=0} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 140

dsolve(diff(y(x),x$5)+2*y(x)=0,y(x), singsol=all)
 

\[ y \left (x \right ) = c_{1} {\mathrm e}^{\frac {\left (-i 2^{\frac {7}{10}} \sqrt {5-\sqrt {5}}+2^{\frac {1}{5}} \sqrt {5}+2^{\frac {1}{5}}\right ) x}{4}}+c_{2} {\mathrm e}^{-\frac {x \left (i \left (\sqrt {5}+1\right ) 2^{\frac {7}{10}} \sqrt {5-\sqrt {5}}+2 \,2^{\frac {1}{5}} \left (\sqrt {5}-1\right )\right )}{8}}+c_{3} {\mathrm e}^{-2^{\frac {1}{5}} x}+c_{4} {\mathrm e}^{\frac {\left (i \left (\sqrt {5}+1\right ) 2^{\frac {7}{10}} \sqrt {5-\sqrt {5}}-2 \,2^{\frac {1}{5}} \left (\sqrt {5}-1\right )\right ) x}{8}}+c_{5} {\mathrm e}^{2^{\frac {1}{5}} \left (\cos \left (\frac {\pi }{5}\right )+i \sin \left (\frac {\pi }{5}\right )\right ) x} \]

Solution by Mathematica

Time used: 0.006 (sec). Leaf size: 180

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

\[ y(x)\to e^{-\frac {\left (\sqrt {5}-1\right ) x}{2\ 2^{4/5}}} \left (c_5 e^{\frac {\left (\sqrt {5}-5\right ) x}{2\ 2^{4/5}}}+c_3 e^{\frac {\sqrt {5} x}{2^{4/5}}} \cos \left (\frac {\sqrt {5-\sqrt {5}} x}{2\ 2^{3/10}}\right )+c_4 \cos \left (\frac {\sqrt {5+\sqrt {5}} x}{2\ 2^{3/10}}\right )+c_2 e^{\frac {\sqrt {5} x}{2^{4/5}}} \sin \left (\frac {\sqrt {5-\sqrt {5}} x}{2\ 2^{3/10}}\right )+c_1 \sin \left (\frac {\sqrt {5+\sqrt {5}} x}{2\ 2^{3/10}}\right )\right ) \]