65.3.9 problem 8.5

Internal problem ID [13656]
Book : AN INTRODUCTION TO ORDINARY DIFFERENTIAL EQUATIONS by JAMES C. ROBINSON. Cambridge University Press 2004
Section : Chapter 8, Separable equations. Exercises page 72
Problem number : 8.5
Date solved : Monday, March 31, 2025 at 08:04:14 AM
CAS classification : [_quadrature]

\begin{align*} x^{\prime }&=\lambda x \end{align*}

✓ Maple. Time used: 0.002 (sec). Leaf size: 10

ode:=diff(x(t),t) = lambda*x(t); 
dsolve(ode,x(t), singsol=all);
 

\[ x = c_1 \,{\mathrm e}^{\lambda t} \]

✓ Mathematica. Time used: 0.023 (sec). Leaf size: 18

ode=D[x[t],t]==\[Lambda]*x[t]; 
ic={}; 
DSolve[{ode,ic},x[t],t,IncludeSingularSolutions->True]
 

\begin{align*} x(t)\to c_1 e^{\lambda t} \\ x(t)\to 0 \\ \end{align*}

✓ Sympy. Time used: 0.095 (sec). Leaf size: 8

from sympy import * 
t = symbols("t") 
lambda_ = symbols("lambda_") 
x = Function("x") 
ode = Eq(-lambda_*x(t) + Derivative(x(t), t),0) 
ics = {} 
dsolve(ode,func=x(t),ics=ics)
 

\[ x{\left (t \right )} = C_{1} e^{\lambda _{} t} \]