5.9 problem 10.4 (ii)

Internal problem ID [11692]

Book: AN INTRODUCTION TO ORDINARY DIFFERENTIAL EQUATIONS by JAMES C. ROBINSON. Cambridge University Press 2004
Section: Chapter 10, Two tricks for nonlinear equations. Exercises page 97
Problem number: 10.4 (ii).
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [[_homogeneous, `class A`], _dAlembert]

\[ \boxed {x^{\prime }-\frac {x^{2}+t \sqrt {x^{2}+t^{2}}}{t x}=0} \]

Solution by Maple

Time used: 0.015 (sec). Leaf size: 24

dsolve(diff(x(t),t)=(x(t)^2+t*sqrt(t^2+x(t)^2))/(t*x(t)),x(t), singsol=all)
 

\[ -\frac {\sqrt {t^{2}+x \left (t \right )^{2}}}{t}+\ln \left (t \right )-c_{1} = 0 \]

Solution by Mathematica

Time used: 0.512 (sec). Leaf size: 54

DSolve[x'[t]==(x[t]^2+t*Sqrt[t^2+x[t]^2])/(t*x[t]),x[t],t,IncludeSingularSolutions -> True]
 

\begin{align*} x(t)\to -t \sqrt {\log ^2(t)+2 c_1 \log (t)-1+c_1{}^2} x(t)\to t \sqrt {\log ^2(t)+2 c_1 \log (t)-1+c_1{}^2} \end{align*}