8.23 problem 23

Internal problem ID [14425]

Book: INTRODUCTORY DIFFERENTIAL EQUATIONS. Martha L. Abell, James P. Braselton. Fourth edition 2014. ElScAe. 2014
Section: Chapter 2. First Order Equations. Review exercises, page 80
Problem number: 23.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_linear]

\[ \boxed {t r^{\prime }+r=\cos \left (t \right ) t} \]

Solution by Maple

Time used: 0.0 (sec). Leaf size: 16

dsolve(t*diff(r(t),t)+r(t)=t*cos(t),r(t), singsol=all)
 

\[ r \left (t \right ) = \frac {\sin \left (t \right ) t +\cos \left (t \right )+c_{1}}{t} \]

Solution by Mathematica

Time used: 0.046 (sec). Leaf size: 18

DSolve[t*r'[t]+r[t]==t*Cos[t],r[t],t,IncludeSingularSolutions -> True]
 

\[ r(t)\to \frac {t \sin (t)+\cos (t)+c_1}{t} \]