3.8 problem 12

Internal problem ID [523]

Book: Elementary differential equations and boundary value problems, 10th ed., Boyce and DiPrima
Section: Section 2.4. Page 76
Problem number: 12.
ODE order: 1.
ODE degree: 1.

CAS Maple gives this as type [_separable]

\[ \boxed {y^{\prime }-\frac {\cot \left (t \right ) y}{1+y}=0} \]

Solution by Maple

Time used: 0.047 (sec). Leaf size: 9

dsolve(diff(y(t),t) = cot(t)*y(t)/(1+y(t)),y(t), singsol=all)
 

\[ y \left (t \right ) = \operatorname {LambertW}\left (c_{1} \sin \left (t \right )\right ) \]

Solution by Mathematica

Time used: 1.602 (sec). Leaf size: 18

DSolve[y'[t] == Cot[t]*y[t]/(1+y[t]),y[t],t,IncludeSingularSolutions -> True]
 

\begin{align*} y(t)\to W\left (e^{c_1} \sin (t)\right ) y(t)\to 0 \end{align*}