9.42 problem 1897

Internal problem ID [9476]

Book: Differential Gleichungen, E. Kamke, 3rd ed. Chelsea Pub. NY, 1948
Section: Chapter 8, system of first order odes
Problem number: 1897.
ODE order: 1.
ODE degree: 1.

Solve \begin {align*} 2 x^{\prime \prime }\relax (t )+y^{\prime \prime }\relax (t )&=2 t\\ x^{\prime \prime }\relax (t )+y^{\prime \prime }\relax (t )+y^{\prime }\relax (t )&=\sinh \left (2 t \right ) \end {align*}

Solution by Maple

Time used: 0.265 (sec). Leaf size: 114

dsolve({diff(x(t),t,t)+diff(y(t),t,t)+diff(y(t),t)=sinh(2*t),2*diff(x(t),t,t)+diff(y(t),t,t)=2*t},{x(t), y(t)}, singsol=all)
 

\[ x \relax (t ) = \frac {t^{2}}{4}+\frac {t^{3}}{6}+\frac {t \sinh \left (2 t \right )}{4}-\frac {3 \cosh \left (2 t \right )}{8}-\frac {t \cosh \left (2 t \right )}{4}+\frac {\sinh \left (2 t \right )}{4}+\frac {\cosh \left (2 t \right ) c_{2}}{4}-\frac {c_{2} \sinh \left (2 t \right )}{4}+c_{3} t +c_{4} \] \[ y \relax (t ) = -\frac {t^{2}}{2}+\frac {t}{2}-\frac {\sinh \left (2 t \right )}{2}+\frac {t \cosh \left (2 t \right )}{2}+\frac {3 \cosh \left (2 t \right )}{4}-\frac {t \sinh \left (2 t \right )}{2}+\frac {c_{2} \sinh \left (2 t \right )}{2}-\frac {\cosh \left (2 t \right ) c_{2}}{2}+c_{3}+c_{1} \]

Solution by Mathematica

Time used: 0.152 (sec). Leaf size: 110

DSolve[{x''[t]+y''[t]+y'[t]==Sinh[2*t],2*x''[t]+y''[t]==2*t},{x[t],y[t]},t,IncludeSingularSolutions -> True]
 

\begin{align*} x(t)\to \frac {1}{48} \left (-3 e^{2 t}-6 e^{-2 t} (2 t+1-2 c_4)+4 t (t (2 t+3)-3+12 c_2+6 c_4)+6+48 c_1-12 c_4\right ) \\ y(t)\to \frac {1}{8} e^{-2 t} \left (4 t+e^{4 t}+e^{2 t} (-4 (t-1) t-2+8 c_3+4 c_4)+2-4 c_4\right ) \\ \end{align*}