1.15 problem 15

Internal problem ID [2049]

Book: Differential equations and linear algebra, Stephen W. Goode, second edition, 2000
Section: 1.4, page 36
Problem number: 15.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_separable]

Solve \begin {gather*} \boxed {y^{\prime }-y^{3} \sin \relax (x )=0} \end {gather*}

Solution by Maple

Time used: 0.006 (sec). Leaf size: 25

dsolve(diff(y(x),x)=y(x)^3*sin(x),y(x), singsol=all)
 

\begin{align*} y \relax (x ) = \frac {1}{\sqrt {c_{1}+2 \cos \relax (x )}} \\ y \relax (x ) = -\frac {1}{\sqrt {c_{1}+2 \cos \relax (x )}} \\ \end{align*}

Solution by Mathematica

Time used: 0.159 (sec). Leaf size: 49

DSolve[y'[x]==y[x]^3*Sin[x],y[x],x,IncludeSingularSolutions -> True]
 

\begin{align*} y(x)\to -\frac {1}{\sqrt {2} \sqrt {\cos (x)-c_1}} \\ y(x)\to \frac {1}{\sqrt {2} \sqrt {\cos (x)-c_1}} \\ y(x)\to 0 \\ \end{align*}