1.15 problem 2(e)

Internal problem ID [2507]

Book: Theory and solutions of Ordinary Differential equations, Donald Greenspan, 1960
Section: Exercises, page 14
Problem number: 2(e).
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_separable]

Solve \begin {gather*} \boxed {{\mathrm e}^{-y}+\left (x^{2}+1\right ) y^{\prime }=0} \end {gather*} With initial conditions \begin {align*} [y \relax (0) = 0] \end {align*}

Solution by Maple

Time used: 0.062 (sec). Leaf size: 11

dsolve([exp(-y(x))+(1+x^2)*diff(y(x),x)=0,y(0) = 0],y(x), singsol=all)
 

\[ y \relax (x ) = \ln \left (-\arctan \relax (x )+1\right ) \]

Solution by Mathematica

Time used: 0.39 (sec). Leaf size: 12

DSolve[{Exp[-y[x]]+(1+x^2)*y'[x]==0,y[0]==0},y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to \log (1-\text {ArcTan}(x)) \\ \end{align*}