Internal problem ID [5973]
Book: An introduction to Ordinary Differential Equations. Earl A. Coddington. Dover. NY
1961
Section: Chapter 2. Linear equations with constant coefficients. Page 74
Problem number: 4(b).
ODE order: 4.
ODE degree: 1.
CAS Maple gives this as type [[_high_order, _missing_x]]
\[ \boxed {y^{\prime \prime \prime \prime }+16 y=0} \]
✓ Solution by Maple
Time used: 0.0 (sec). Leaf size: 65
dsolve(diff(y(x),x$4)+16*y(x)=0,y(x), singsol=all)
\[ y \left (x \right ) = -c_{1} {\mathrm e}^{-\sqrt {2}\, x} \sin \left (\sqrt {2}\, x \right )-c_{2} {\mathrm e}^{\sqrt {2}\, x} \sin \left (\sqrt {2}\, x \right )+c_{3} {\mathrm e}^{-\sqrt {2}\, x} \cos \left (\sqrt {2}\, x \right )+c_{4} {\mathrm e}^{\sqrt {2}\, x} \cos \left (\sqrt {2}\, x \right ) \]
✓ Solution by Mathematica
Time used: 0.004 (sec). Leaf size: 67
DSolve[y''''[x]+16*y[x]==0,y[x],x,IncludeSingularSolutions -> True]
\[ y(x)\to e^{-\sqrt {2} x} \left (\left (c_1 e^{2 \sqrt {2} x}+c_2\right ) \cos \left (\sqrt {2} x\right )+\left (c_4 e^{2 \sqrt {2} x}+c_3\right ) \sin \left (\sqrt {2} x\right )\right ) \]