17.1.1 problem 1(a)

Internal problem ID [4091]
Book : Theory and solutions of Ordinary Differential equations, Donald Greenspan, 1960
Section : Chapter 2. First order equations. Exercises at page 14
Problem number : 1(a)
Date solved : Tuesday, September 30, 2025 at 07:02:32 AM
CAS classification : [_quadrature]

\begin{align*} y^{\prime }&={\mathrm e}^{-x} \end{align*}

✓ Maple. Time used: 0.001 (sec). Leaf size: 12

ode:=diff(y(x),x) = exp(-x); 
dsolve(ode,y(x), singsol=all);
 

\[ y = -{\mathrm e}^{-x}+c_1 \]

✓ Mathematica. Time used: 0.003 (sec). Leaf size: 15

ode=D[y[x],x]==Exp[-x]; 
ic={}; 
DSolve[{ode,ic},y[x],x,IncludeSingularSolutions->True]
 

\begin{align*} y(x)&\to -e^{-x}+c_1 \end{align*}

✓ Sympy. Time used: 0.065 (sec). Leaf size: 8

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

\[ y{\left (x \right )} = C_{1} - e^{- x} \]